MediaProjectionDemo.java

/*
 * Copyright (C) 2014 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.example.android.apis.media.projection;

import com.example.android.apis.R;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.res.Configuration;
import android.hardware.display.DisplayManager;
import android.hardware.display.VirtualDisplay;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjectionManager;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.Toast;
import android.widget.ToggleButton;

import java.util.ArrayList;
import java.util.List;

public class MediaProjectionDemo extends Activity {
    private static final String TAG = "MediaProjectionDemo";
    private static final int PERMISSION_CODE = 1;
    private static final List<Resolution> RESOLUTIONS = new ArrayList<Resolution>() {{
        add(new Resolution(640,360));
        add(new Resolution(960,540));
        add(new Resolution(1366,768));
        add(new Resolution(1600,900));
    }};

    private int mScreenDensity;
    private MediaProjectionManager mProjectionManager;

    private int mDisplayWidth;
    private int mDisplayHeight;
    private boolean mScreenSharing;

    private MediaProjection mMediaProjection;
    private VirtualDisplay mVirtualDisplay;
    private Surface mSurface;
    private SurfaceView mSurfaceView;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.media_projection);

        DisplayMetrics metrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(metrics);
        mScreenDensity = metrics.densityDpi;

        mSurfaceView = (SurfaceView) findViewById(R.id.surface);
        mSurface = mSurfaceView.getHolder().getSurface();
        mProjectionManager =
            (MediaProjectionManager) getSystemService(Context.MEDIA_PROJECTION_SERVICE);

        ArrayAdapter<Resolution> arrayAdapter = new ArrayAdapter<Resolution>(
                this, android.R.layout.simple_list_item_1, RESOLUTIONS);
        Spinner s = (Spinner) findViewById(R.id.spinner);
        s.setAdapter(arrayAdapter);
        s.setOnItemSelectedListener(new ResolutionSelector());
        s.setSelection(0);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mMediaProjection != null) {
            mMediaProjection.stop();
            mMediaProjection = null;
        }
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode != PERMISSION_CODE) {
            Log.e(TAG, "Unknown request code: " + requestCode);
            return;
        }
        if (resultCode != RESULT_OK) {
            Toast.makeText(this,
                    "User denied screen sharing permission", Toast.LENGTH_SHORT).show();
            return;
        }
        mMediaProjection = mProjectionManager.getMediaProjection(resultCode, data);
        mVirtualDisplay = createVirtualDisplay();
    }

    public void onToggleScreenShare(View view) {
        if (((ToggleButton) view).isChecked()) {
            shareScreen();
        } else {
            stopScreenSharing();
        }
    }

    private void shareScreen() {
        mScreenSharing = true;
        if (mSurface == null) {
            return;
        }
        if (mMediaProjection == null) {
            startActivityForResult(mProjectionManager.createScreenCaptureIntent(),
                    PERMISSION_CODE);
            return;
        }
        mVirtualDisplay = createVirtualDisplay();
    }

    private void stopScreenSharing() {
        mScreenSharing = false;
        if (mVirtualDisplay == null) {
            return;
        }
        mVirtualDisplay.release();
    }

    private VirtualDisplay createVirtualDisplay() {
        return mMediaProjection.createVirtualDisplay("ScreenSharingDemo",
                mDisplayWidth, mDisplayHeight, mScreenDensity,
                DisplayManager.VIRTUAL_DISPLAY_FLAG_AUTO_MIRROR,
                mSurface, null /*Callbacks*/, null /*Handler*/);
    }

    private void resizeVirtualDisplay() {
        if (mVirtualDisplay == null) {
            return;
        }
        mVirtualDisplay.resize(mDisplayWidth, mDisplayHeight, mScreenDensity);
    }

    private class ResolutionSelector implements Spinner.OnItemSelectedListener {
        @Override
        public void onItemSelected(AdapterView<?> parent, View v, int pos, long id) {
            Resolution r = (Resolution) parent.getItemAtPosition(pos);
            ViewGroup.LayoutParams lp = mSurfaceView.getLayoutParams();
            if (getResources().getConfiguration().orientation
                    == Configuration.ORIENTATION_LANDSCAPE) {
                mDisplayHeight = r.y;
                mDisplayWidth = r.x;
            } else {
                mDisplayHeight = r.x;
                mDisplayWidth = r.y;
            }
            lp.height = mDisplayHeight;
            lp.width = mDisplayWidth;
            mSurfaceView.setLayoutParams(lp);
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) { /* Ignore */ }
    }

    private class MediaProjectionCallback extends MediaProjection.Callback {
        @Override
        public void onStop() {
            mMediaProjection = null;
            stopScreenSharing();
        }
    }

    private class SurfaceCallbacks implements SurfaceHolder.Callback {
        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
            mDisplayWidth = width;
            mDisplayHeight = height;
            resizeVirtualDisplay();
        }

        @Override
        public void surfaceCreated(SurfaceHolder holder) {
            mSurface = holder.getSurface();
            if (mScreenSharing) {
                shareScreen();
            }
        }

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {
            if (!mScreenSharing) {
                stopScreenSharing();
            }
        }
    }

    private static class Resolution {
        int x;
        int y;

        public Resolution(int x, int y) {
            this.x = x;
            this.y = y;
        }

        @Override
        public String toString() {
            return x + "x" + y;
        }
    }
}