Added API to mirror display and added sample app.

Added the WMS.mirrorDisplay API to mirror a specified displayId. The
request requires the ACCESS_SURFACE_FLINGER permission.

Added a sample app to demonstrate the useablility of this API and
different ways the mirror SurfaceControl can be used.

Test: mmma tests/MirrorSurfaceTest and install apk
Bug: 131622422
Change-Id: Ic86115786d37473650b3c7ed39cba0bd4c65b281

5 files changed, 693 insertions, 0 deletions

diff --git a/tests/MirrorSurfaceTest/Android.bp b/tests/MirrorSurfaceTest/Android.bp
new file mode 100644
index 000000000000..e359c64cc982
--- /dev/null
+++ b/tests/MirrorSurfaceTest/Android.bp
@@ -0,0 +1,6 @@
+android_test {
+    name: "MirrorSurfaceTest",
+    srcs: ["src/**/*.java"],
+    platform_apis: true,
+    certificate: "platform",
+}
diff --git a/tests/MirrorSurfaceTest/AndroidManifest.xml b/tests/MirrorSurfaceTest/AndroidManifest.xml
new file mode 100644
index 000000000000..123cd0f26ff3
--- /dev/null
+++ b/tests/MirrorSurfaceTest/AndroidManifest.xml
@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2019 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="com.google.android.test.mirrorsurface">
+    <uses-permission android:name="android.permission.ACCESS_SURFACE_FLINGER"/>
+    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
+
+    <application android:label="MirrorSurfaceTest">
+        <activity android:name=".MirrorSurfaceActivity"
+                  android:label="Mirror Surface"
+                  android:configChanges="orientation|screenSize">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+                <category android:name="android.intent.category.DEFAULT"/>
+            </intent-filter>
+        </activity>
+    </application>
+</manifest>
diff --git a/tests/MirrorSurfaceTest/res/layout/activity_mirror_surface.xml b/tests/MirrorSurfaceTest/res/layout/activity_mirror_surface.xml
new file mode 100644
index 000000000000..73b509f743d1
--- /dev/null
+++ b/tests/MirrorSurfaceTest/res/layout/activity_mirror_surface.xml
@@ -0,0 +1,111 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2019 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+              android:layout_width="match_parent"
+              android:layout_height="match_parent"
+              android:orientation="vertical">
+
+    <LinearLayout
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="center_horizontal"
+        android:layout_marginTop="20dp"
+        android:orientation="horizontal">
+
+        <Button
+            android:id="@+id/mirror_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginRight="20dp"
+            android:text="Mirror"
+            android:textSize="20dp" />
+
+        <Button
+            android:id="@+id/remove_mirror_button"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginRight="20dp"
+            android:text="Remove Mirror"
+            android:textSize="20dp" />
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginLeft="40dp"
+        android:layout_marginRight="40dp"
+        android:layout_marginTop="10dp"
+        android:orientation="horizontal">
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginRight="20dp"
+            android:text="SCALE: " />
+
+        <EditText
+            android:hint="0.5"
+            android:id="@+id/scale"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="numberDecimal" />
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginLeft="40dp"
+        android:layout_marginRight="40dp"
+        android:layout_marginTop="10dp"
+        android:orientation="horizontal">
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginRight="20dp"
+            android:text="DISPLAY FRAME: " />
+
+        <EditText
+            android:hint="0, 0, 20, 20"
+            android:id="@+id/displayFrame"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="numberDecimal|text"/>
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginLeft="40dp"
+        android:layout_marginRight="40dp"
+        android:layout_marginTop="10dp"
+        android:orientation="horizontal">
+
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginRight="20dp"
+            android:text="SOURCE POSITION: " />
+
+        <TextView
+            android:id="@+id/sourcePosition"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:inputType="numberDecimal|text"/>
+    </LinearLayout>
+</LinearLayout>
diff --git a/tests/MirrorSurfaceTest/res/layout/move_view.xml b/tests/MirrorSurfaceTest/res/layout/move_view.xml
new file mode 100644
index 000000000000..57077006765e
--- /dev/null
+++ b/tests/MirrorSurfaceTest/res/layout/move_view.xml
@@ -0,0 +1,101 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2019 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+             android:layout_width="wrap_content"
+             android:layout_height="wrap_content"
+             android:layout_margin="20dp"
+             android:gravity="center">
+
+    <RelativeLayout
+        android:id="@+id/arrows"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content">
+
+        <ImageButton
+            android:id="@+id/up_arrow"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_toEndOf="@+id/right_arrow"
+            android:background="@android:color/holo_green_light"
+            android:padding="10dp"
+            android:src="@android:drawable/arrow_up_float" />
+
+        <ImageButton
+            android:id="@+id/down_arrow"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_below="@+id/up_arrow"
+            android:layout_marginTop="80dp"
+            android:layout_toEndOf="@+id/right_arrow"
+            android:background="@android:color/holo_green_light"
+            android:padding="10dp"
+            android:src="@android:drawable/arrow_down_float" />
+
+        <ImageButton
+            android:id="@+id/right_arrow"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignTop="@+id/up_arrow"
+            android:layout_alignBottom="@+id/down_arrow"
+            android:layout_marginTop="55dp"
+            android:layout_marginEnd="15dp"
+            android:layout_marginBottom="55dp"
+            android:background="@android:color/holo_green_light"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp"
+            android:rotation="90"
+            android:src="@android:drawable/arrow_down_float" />
+
+        <ImageButton
+            android:id="@+id/left_arrow"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_alignTop="@+id/up_arrow"
+            android:layout_alignBottom="@+id/down_arrow"
+            android:layout_marginStart="15dp"
+            android:layout_marginTop="55dp"
+            android:layout_marginBottom="55dp"
+            android:layout_toEndOf="@+id/down_arrow"
+            android:background="@android:color/holo_green_light"
+            android:paddingLeft="10dp"
+            android:paddingRight="10dp"
+            android:rotation="-90"
+            android:src="@android:drawable/arrow_down_float" />
+    </RelativeLayout>
+
+    <RelativeLayout
+
+        android:layout_gravity="center"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content">
+
+        <Button
+            android:id="@+id/zoom_in_button"
+            android:layout_width="40dp"
+            android:layout_marginBottom="-8dp"
+            android:layout_height="40dp"
+            android:text="+" />
+
+        <Button
+            android:layout_below="@+id/zoom_in_button"
+            android:id="@+id/zoom_out_button"
+            android:layout_width="40dp"
+            android:layout_height="40dp"
+            android:text="-" />
+    </RelativeLayout>
+</FrameLayout>
\ No newline at end of file
diff --git a/tests/MirrorSurfaceTest/src/com/google/android/test/mirrorsurface/MirrorSurfaceActivity.java b/tests/MirrorSurfaceTest/src/com/google/android/test/mirrorsurface/MirrorSurfaceActivity.java
new file mode 100644
index 000000000000..b863713df15b
--- /dev/null
+++ b/tests/MirrorSurfaceTest/src/com/google/android/test/mirrorsurface/MirrorSurfaceActivity.java
@@ -0,0 +1,441 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.android.test.mirrorsurface;
+
+
+import android.app.Activity;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.PixelFormat;
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.RemoteException;
+import android.util.DisplayMetrics;
+import android.view.Gravity;
+import android.view.IWindowManager;
+import android.view.MotionEvent;
+import android.view.Surface;
+import android.view.SurfaceControl;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.WindowManager;
+import android.view.WindowManagerGlobal;
+import android.widget.EditText;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+public class MirrorSurfaceActivity extends Activity implements View.OnClickListener,
+        View.OnLongClickListener, View.OnTouchListener {
+    private static final int BORDER_SIZE = 10;
+    private static final int DEFAULT_SCALE = 2;
+    private static final int DEFAULT_BORDER_COLOR = Color.argb(255, 255, 153, 0);
+    private static final int MOVE_FRAME_AMOUNT = 20;
+
+    private IWindowManager mIWm;
+    private WindowManager mWm;
+
+    private SurfaceControl mSurfaceControl = new SurfaceControl();
+    private SurfaceControl mBorderSc;
+
+    private SurfaceControl.Transaction mTransaction = new SurfaceControl.Transaction();
+    private View mOverlayView;
+    private View mArrowOverlay;
+
+    private Rect mDisplayBounds = new Rect();
+
+    private EditText mScaleText;
+    private EditText mDisplayFrameText;
+    private TextView mSourcePositionText;
+
+    private Rect mTmpRect = new Rect();
+    private final Surface mTmpSurface = new Surface();
+
+    private boolean mHasMirror;
+
+    private Rect mCurrFrame = new Rect();
+    private float mCurrScale = DEFAULT_SCALE;
+
+    private final Handler mHandler = new Handler();
+
+    private MoveMirrorRunnable mMoveMirrorRunnable = new MoveMirrorRunnable();
+    private boolean mIsPressedDown = false;
+
+    private int mDisplayId;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        setContentView(R.layout.activity_mirror_surface);
+        mWm = (WindowManager) getSystemService(WINDOW_SERVICE);
+        mIWm = WindowManagerGlobal.getWindowManagerService();
+
+        DisplayMetrics displayMetrics = new DisplayMetrics();
+        getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
+        mDisplayBounds.set(0, 0, displayMetrics.widthPixels, displayMetrics.heightPixels);
+
+        mScaleText = findViewById(R.id.scale);
+        mDisplayFrameText = findViewById(R.id.displayFrame);
+        mSourcePositionText = findViewById(R.id.sourcePosition);
+
+        mCurrFrame.set(0, 0, mDisplayBounds.width() / 2, mDisplayBounds.height() / 2);
+        mCurrScale = DEFAULT_SCALE;
+
+        mDisplayId = getWindowManager().getDefaultDisplay().getDisplayId();
+        updateEditTexts();
+
+        findViewById(R.id.mirror_button).setOnClickListener(view -> {
+            if (mArrowOverlay == null) {
+                createArrowOverlay();
+            }
+            createOrUpdateMirror();
+        });
+
+        findViewById(R.id.remove_mirror_button).setOnClickListener(v -> {
+            removeMirror();
+            removeArrowOverlay();
+        });
+
+        createMirrorOverlay();
+    }
+
+    private void updateEditTexts() {
+        mDisplayFrameText.setText(
+                String.format("%s, %s, %s, %s", mCurrFrame.left, mCurrFrame.top, mCurrFrame.right,
+                        mCurrFrame.bottom));
+        mScaleText.setText(String.valueOf(mCurrScale));
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        if (mOverlayView != null) {
+            removeMirror();
+            mWm.removeView(mOverlayView);
+            mOverlayView = null;
+        }
+        removeArrowOverlay();
+    }
+
+    private void createArrowOverlay() {
+        mArrowOverlay = getLayoutInflater().inflate(R.layout.move_view, null);
+        WindowManager.LayoutParams arrowParams = new WindowManager.LayoutParams(
+                ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT,
+                WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
+                WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL
+                        | WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
+                        | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
+                PixelFormat.RGBA_8888);
+        arrowParams.gravity = Gravity.RIGHT | Gravity.BOTTOM;
+        mWm.addView(mArrowOverlay, arrowParams);
+
+        View leftArrow = mArrowOverlay.findViewById(R.id.left_arrow);
+        View topArrow = mArrowOverlay.findViewById(R.id.up_arrow);
+        View rightArrow = mArrowOverlay.findViewById(R.id.right_arrow);
+        View bottomArrow = mArrowOverlay.findViewById(R.id.down_arrow);
+
+        leftArrow.setOnClickListener(this);
+        topArrow.setOnClickListener(this);
+        rightArrow.setOnClickListener(this);
+        bottomArrow.setOnClickListener(this);
+
+        leftArrow.setOnLongClickListener(this);
+        topArrow.setOnLongClickListener(this);
+        rightArrow.setOnLongClickListener(this);
+        bottomArrow.setOnLongClickListener(this);
+
+        leftArrow.setOnTouchListener(this);
+        topArrow.setOnTouchListener(this);
+        rightArrow.setOnTouchListener(this);
+        bottomArrow.setOnTouchListener(this);
+
+        mArrowOverlay.findViewById(R.id.zoom_in_button).setOnClickListener(v -> {
+            if (mCurrScale <= 1) {
+                mCurrScale *= 2;
+            } else {
+                mCurrScale += 0.5;
+            }
+
+            updateMirror(mCurrFrame, mCurrScale);
+        });
+        mArrowOverlay.findViewById(R.id.zoom_out_button).setOnClickListener(v -> {
+            if (mCurrScale <= 1) {
+                mCurrScale /= 2;
+            } else {
+                mCurrScale -= 0.5;
+            }
+
+            updateMirror(mCurrFrame, mCurrScale);
+        });
+    }
+
+    private void removeArrowOverlay() {
+        if (mArrowOverlay != null) {
+            mWm.removeView(mArrowOverlay);
+            mArrowOverlay = null;
+        }
+    }
+
+    private void createMirrorOverlay() {
+        mOverlayView = new LinearLayout(this);
+        WindowManager.LayoutParams params = new WindowManager.LayoutParams(mDisplayBounds.width(),
+                mDisplayBounds.height(),
+                WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY,
+                WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE
+                        | WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
+                PixelFormat.RGBA_8888);
+        params.gravity = Gravity.LEFT | Gravity.TOP;
+        params.setTitle("Mirror Overlay");
+        mOverlayView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
+                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
+                | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
+                | View.SYSTEM_UI_FLAG_FULLSCREEN
+                | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
+                | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
+
+        mWm.addView(mOverlayView, params);
+
+    }
+
+    private void removeMirror() {
+        if (mSurfaceControl.isValid()) {
+            mTransaction.remove(mSurfaceControl).apply();
+        }
+        mHasMirror = false;
+    }
+
+    private void createOrUpdateMirror() {
+        if (mHasMirror) {
+            updateMirror(getDisplayFrame(), getScale());
+        } else {
+            createMirror(getDisplayFrame(), getScale());
+        }
+
+    }
+
+    private Rect getDisplayFrame() {
+        mTmpRect.setEmpty();
+        String[] frameVals = mDisplayFrameText.getText().toString().split("\\s*,\\s*");
+        if (frameVals.length != 4) {
+            return mTmpRect;
+        }
+
+        try {
+            mTmpRect.set(Integer.parseInt(frameVals[0]), Integer.parseInt(frameVals[1]),
+                    Integer.parseInt(frameVals[2]), Integer.parseInt(frameVals[3]));
+        } catch (Exception e) {
+            mTmpRect.setEmpty();
+        }
+
+        return mTmpRect;
+    }
+
+    private float getScale() {
+        try {
+            return Float.parseFloat(mScaleText.getText().toString());
+        } catch (Exception e) {
+            return -1;
+        }
+    }
+
+    private void createMirror(Rect displayFrame, float scale) {
+        boolean success = false;
+        try {
+            success = mIWm.mirrorDisplay(mDisplayId, mSurfaceControl);
+        } catch (RemoteException e) {
+        }
+
+        if (!success) {
+            return;
+        }
+
+        if (!mSurfaceControl.isValid()) {
+            return;
+        }
+
+        mHasMirror = true;
+
+        mBorderSc = new SurfaceControl.Builder()
+                .setName("Mirror Border")
+                .setBufferSize(1, 1)
+                .setFormat(PixelFormat.TRANSLUCENT)
+                .build();
+
+        updateMirror(displayFrame, scale);
+
+        mTransaction
+                .show(mSurfaceControl)
+                .reparent(mSurfaceControl, mOverlayView.getViewRootImpl().getSurfaceControl())
+                .setLayer(mBorderSc, 1)
+                .show(mBorderSc)
+                .reparent(mBorderSc, mSurfaceControl)
+                .apply();
+    }
+
+    private void updateMirror(Rect displayFrame, float scale) {
+        if (displayFrame.isEmpty()) {
+            Rect bounds = mDisplayBounds;
+            int defaultCropW = Math.round(bounds.width() / 2);
+            int defaultCropH = Math.round(bounds.height() / 2);
+            displayFrame.set(0, 0, defaultCropW, defaultCropH);
+        }
+
+        if (scale <= 0) {
+            scale = DEFAULT_SCALE;
+        }
+
+        mCurrFrame.set(displayFrame);
+        mCurrScale = scale;
+
+        int width = (int) Math.ceil(displayFrame.width() / scale);
+        int height = (int) Math.ceil(displayFrame.height() / scale);
+
+        Rect sourceBounds = getSourceBounds(displayFrame, scale);
+
+        mTransaction.setGeometry(mSurfaceControl, sourceBounds, displayFrame, Surface.ROTATION_0)
+                .setPosition(mBorderSc, sourceBounds.left, sourceBounds.top)
+                .setBufferSize(mBorderSc, width, height)
+                .apply();
+
+        drawBorder(mBorderSc, width, height, (int) Math.ceil(BORDER_SIZE / scale));
+
+        mSourcePositionText.setText(sourceBounds.left + ", " + sourceBounds.top);
+        mDisplayFrameText.setText(
+                String.format("%s, %s, %s, %s", mCurrFrame.left, mCurrFrame.top, mCurrFrame.right,
+                        mCurrFrame.bottom));
+        mScaleText.setText(String.valueOf(mCurrScale));
+    }
+
+    private void drawBorder(SurfaceControl borderSc, int width, int height, int borderSize) {
+        mTmpSurface.copyFrom(borderSc);
+
+        Canvas c = null;
+        try {
+            c = mTmpSurface.lockCanvas(null);
+        } catch (IllegalArgumentException | Surface.OutOfResourcesException e) {
+        }
+        if (c == null) {
+            return;
+        }
+
+        // Top
+        c.save();
+        c.clipRect(new Rect(0, 0, width, borderSize));
+        c.drawColor(DEFAULT_BORDER_COLOR);
+        c.restore();
+        // Left
+        c.save();
+        c.clipRect(new Rect(0, 0, borderSize, height));
+        c.drawColor(DEFAULT_BORDER_COLOR);
+        c.restore();
+        // Right
+        c.save();
+        c.clipRect(new Rect(width - borderSize, 0, width, height));
+        c.drawColor(DEFAULT_BORDER_COLOR);
+        c.restore();
+        // Bottom
+        c.save();
+        c.clipRect(new Rect(0, height - borderSize, width, height));
+        c.drawColor(DEFAULT_BORDER_COLOR);
+        c.restore();
+
+        mTmpSurface.unlockCanvasAndPost(c);
+    }
+
+    @Override
+    public void onClick(View v) {
+        Point offset = findOffset(v);
+        moveMirrorForArrows(offset.x, offset.y);
+    }
+
+    @Override
+    public boolean onLongClick(View v) {
+        mIsPressedDown = true;
+        Point point = findOffset(v);
+        mMoveMirrorRunnable.mXOffset = point.x;
+        mMoveMirrorRunnable.mYOffset = point.y;
+        mHandler.post(mMoveMirrorRunnable);
+        return false;
+    }
+
+    @Override
+    public boolean onTouch(View v, MotionEvent event) {
+        switch (event.getAction()) {
+            case MotionEvent.ACTION_UP:
+            case MotionEvent.ACTION_CANCEL:
+                mIsPressedDown = false;
+                break;
+        }
+        return false;
+    }
+
+    private Point findOffset(View v) {
+        Point offset = new Point(0, 0);
+
+        switch (v.getId()) {
+            case R.id.up_arrow:
+                offset.y = -MOVE_FRAME_AMOUNT;
+                break;
+            case R.id.down_arrow:
+                offset.y = MOVE_FRAME_AMOUNT;
+                break;
+            case R.id.right_arrow:
+                offset.x = -MOVE_FRAME_AMOUNT;
+                break;
+            case R.id.left_arrow:
+                offset.x = MOVE_FRAME_AMOUNT;
+                break;
+        }
+
+        return offset;
+    }
+
+    private void moveMirrorForArrows(int xOffset, int yOffset) {
+        mCurrFrame.offset(xOffset, yOffset);
+
+        updateMirror(mCurrFrame, mCurrScale);
+    }
+
+    /**
+     * Calculates the desired source bounds. This will be the area under from the center of  the
+     * displayFrame, factoring in scale.
+     */
+    private Rect getSourceBounds(Rect displayFrame, float scale) {
+        int halfWidth = displayFrame.width() / 2;
+        int halfHeight = displayFrame.height() / 2;
+        int left = displayFrame.left + (halfWidth - (int) (halfWidth / scale));
+        int right = displayFrame.right - (halfWidth - (int) (halfWidth / scale));
+        int top = displayFrame.top + (halfHeight - (int) (halfHeight / scale));
+        int bottom = displayFrame.bottom - (halfHeight - (int) (halfHeight / scale));
+        return new Rect(left, top, right, bottom);
+    }
+
+    class MoveMirrorRunnable implements Runnable {
+        int mXOffset = 0;
+        int mYOffset = 0;
+
+        @Override
+        public void run() {
+            if (mIsPressedDown) {
+                moveMirrorForArrows(mXOffset, mYOffset);
+                mHandler.postDelayed(mMoveMirrorRunnable, 150);
+            }
+        }
+    }
+}