出處：
炎之鎧郵箱：yanzhikai_yjk@qq.com
博客地址：http://blog.csdn.net/totond
本文原創(chuàng)，轉(zhuǎn)載請注明本出處！
本項目GitHub地址：https://github.com/totond/GestureTest
前言
現(xiàn)在很多全屏的視頻播放器現(xiàn)在都有這樣的功能：左邊上下滑動調(diào)節(jié)亮度，右邊上下滑動調(diào)節(jié)音量，左右滑動調(diào)節(jié)快進快退，雙擊控制暫停播放。實現(xiàn)這樣的功能并不難，本文分享一下實現(xiàn)經(jīng)驗。
實現(xiàn)
本實現(xiàn)采用GestureDetector來處理輸入的手勢，它的介紹可以看我的GestureDetector全面分析，在這里就不詳細講它的用法了。對于GestureDetector的回調(diào)，我們還要把它封裝才能區(qū)分出那些上下左右的手勢，所以這里繼承一個RelativeLayout來封裝它們。下面只介紹了具體實現(xiàn)思路，想開具體細節(jié)的可以進入demo查看。
對GestureDetector的封裝
主要是把onScroll()滑動回調(diào)分成3個部分：音量、手勢和快進快退，所以最后開放給外部的接口是這樣的：
/**
* 用于提供給外部實現(xiàn)的視頻手勢處理接口
*/
public interface VideoGestureListener {
//亮度手勢，手指在Layout左半部上下滑動時候調(diào)用
public void onBrightnessGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY);
//音量手勢，手指在Layout右半部上下滑動時候調(diào)用
public void onVolumeGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY);
//快進快退手勢，手指在Layout左右滑動的時候調(diào)用
public void onFF_REWGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY);
//單擊手勢，確認是單擊的時候調(diào)用
public void onSingleTapGesture(MotionEvent e);
//雙擊手勢，確認是雙擊的時候調(diào)用
public void onDoubleTapGesture(MotionEvent e);
//按下手勢，第一根手指按下時候調(diào)用
public void onDown(MotionEvent e);
//快進快退執(zhí)行后的松開時候調(diào)用
public void onEndFF_REW(MotionEvent e);
}
為了給onScroll()分成3個部分，這里采用一個小小的狀態(tài)模式，給它定義4個狀態(tài)：NONE,VOLUME,BRIGHTNESS,FF_REW。只有NONE狀態(tài)才能進入其他狀態(tài)，其它狀態(tài)一旦進入了不可切換，這樣就保證了用戶劃著音量的時候不會突然就平移就改變了進度：
public class VideoPlayerOnGestureListener extends GestureDetector.SimpleOnGestureListener {
//...
@Override
public boolean onDown(MotionEvent e) {
Log.d(TAG, "onDown: ");
//每次按下都重置為NONE
mScrollMode = NONE;
if (mVideoGestureListener != null) {
mVideoGestureListener.onDown(e);
}
return true;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
Log.d(TAG, "onScroll: e1:" + e1.getX() + "," + e1.getY());
Log.d(TAG, "onScroll: e2:" + e2.getX() + "," + e2.getY());
Log.d(TAG, "onScroll: X:" + distanceX + " Y:" + distanceY);
switch (mScrollMode) {
case NONE:
Log.d(TAG, "NONE: ");
//offset是讓快進快退不要那么敏感的值
if (Math.abs(distanceX) - Math.abs(distanceY) > offsetX) {
mScrollMode = FF_REW;
} else {
if (e1.getX() < getWidth() / 2) {
mScrollMode = BRIGHTNESS;
} else {
mScrollMode = VOLUME;
}
}
break;
case VOLUME:
if (mVideoGestureListener != null) {
mVideoGestureListener.onVolumeGesture(e1, e2, distanceX, distanceY);
}
Log.d(TAG, "VOLUME: ");
break;
case BRIGHTNESS:
if (mVideoGestureListener != null) {
mVideoGestureListener.onBrightnessGesture(e1, e2, distanceX, distanceY);
}
Log.d(TAG, "BRIGHTNESS: ");
break;
case FF_REW:
if (mVideoGestureListener != null) {
mVideoGestureListener.onFF_REWGesture(e1, e2, distanceX, distanceY);
}
hasFF_REW = true;
Log.d(TAG, "FF_REW: ");
break;
}
return true;
}
//...
}
然后在RelativeLayout里面使用這個VideoPlayerOnGestureListener，就讓它們綁定了，只要在Activity里面使用這個RelativeLayout，就可以使用前面的VideoGestureListener接口的回調(diào)了。
public class VideoGestureRelativeLayout extends RelativeLayout {
//...
public VideoGestureRelativeLayout(Context context) {
super(context);
init(context);
}
public VideoGestureRelativeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
private void init(Context context){
mOnGestureListener = new VideoPlayerOnGestureListener(this);
mGestureDetector = new GestureDetector(context,mOnGestureListener);
//取消長按，不然會影響滑動
mGestureDetector.setIsLongpressEnabled(false);
setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
//實現(xiàn)快進快退松開時候的回調(diào)
if (event.getAction() == MotionEvent.ACTION_UP){
if (hasFF_REW){
if (mVideoGestureListener != null) {
mVideoGestureListener.onEndFF_REW(event);
}
hasFF_REW = false;
}
}
//監(jiān)聽觸摸事件
return mGestureDetector.onTouchEvent(event);
}
});
}
//...
}
由于GestureDetector沒有滑動之后松開的回調(diào)，這里在onTouch()方補一個回調(diào)。
具體控制實現(xiàn)
來到這里，接口已經(jīng)做好了，用戶的手勢我們都收到相應(yīng)的回調(diào)了，然后我們要做的是定義收到這些回調(diào)的時候的操作。
中間顯示框
在這里我做了一個比較丑的中間顯示框，里面包含著一個ImageView和一個ProgressBar，默認延時一秒后消失：
/**
* Author: yanzhikai
* Description: 中間用于顯示狀態(tài)的Layout
* Email: yanzhikai_yjk@qq.com
*/
public class ShowChangeLayout extends RelativeLayout {
private static final String TAG = "gesturetest";
private ImageView iv_center;
private ProgressBar pb;
private HideRunnable mHideRunnable;
private int duration = 1000;
public ShowChangeLayout(Context context) {
super(context);
init(context);
}
public ShowChangeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
private void init(Context context){
LayoutInflater.from(context).inflate(R.layout.show_change_layout,this);
iv_center = (ImageView) findViewById(R.id.iv_center);
pb = (ProgressBar) findViewById(R.id.pb);
mHideRunnable = new HideRunnable();
ShowChangeLayout.this.setVisibility(GONE);
}
//顯示
public void show(){
setVisibility(VISIBLE);
removeCallbacks(mHideRunnable);
postDelayed(mHideRunnable,duration);
}
//設(shè)置進度
public void setProgress(int progress){
pb.setProgress(progress);
Log.d(TAG, "setProgress: " +progress);
}
//設(shè)置持續(xù)時間
public void setDuration(int duration) {
this.duration = duration;
}
//設(shè)置顯示圖片
public void setImageResource(int resource){
iv_center.setImageResource(resource);
}
//隱藏自己的Runnable
private class HideRunnable implements Runnable{
@Override
public void run() {
ShowChangeLayout.this.setVisibility(GONE);
}
}
}
亮度、音量、進度調(diào)節(jié)
首先是進行初始化：
public class MainActivity extends AppCompatActivity implements VideoGestureRelativeLayout.VideoGestureListener {
private final String TAG = "gesturetestm";
private VideoGestureRelativeLayout ly_VG;
private ShowChangeLayout scl;
private AudioManager mAudioManager;
private int maxVolume = 0;
private int oldVolume = 0;
private int newProgress = 0, oldProgress = 0;
private BrightnessHelper mBrightnessHelper;
private float brightness = 1;
private Window mWindow;
private WindowManager.LayoutParams mLayoutParams;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ly_VG = (VideoGestureRelativeLayout) findViewById(R.id.ly_VG);
ly_VG.setVideoGestureListener(this);
scl = (ShowChangeLayout) findViewById(R.id.scl);
//初始化獲取音量屬性
mAudioManager = (AudioManager)getSystemService(Service.AUDIO_SERVICE);
maxVolume = mAudioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
//初始化亮度調(diào)節(jié)
mBrightnessHelper = new BrightnessHelper(this);
//下面這是設(shè)置當前APP亮度的方法配置
mWindow = getWindow();
mLayoutParams = mWindow.getAttributes();
brightness = mLayoutParams.screenBrightness;
}
@Override
public void onDown(MotionEvent e) {
//每次按下的時候更新當前亮度和音量，還有進度
oldProgress = newProgress;
oldVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
brightness = mLayoutParams.screenBrightness;
if (brightness == -1){
//一開始是默認亮度的時候，獲取系統(tǒng)亮度，計算比例值
brightness = mBrightnessHelper.getBrightness() / 255f;
}
}
//...
}
每次onDown()都更新3個值的原因：onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)是每次Move事件位移大于1像素都會執(zhí)行的（原因可看上一篇源碼分析），distanceX和distanceY是兩個MOVE之間的距離決定的，如果手指移動得比較慢，它們就會比較小，float轉(zhuǎn)化成int很可能會被舍去小數(shù)點后的然后變成0，讓用戶不能慢慢通過滑動精準調(diào)控參數(shù)，所以要使用e2和e1的位移差來決定亮度等參數(shù)的變化大小，從而就要在onDown()獲取舊數(shù)值來作為起始點了，詳細邏輯請看代碼：
//...
@Override
public void onVolumeGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
int value = ly_VG.getHeight()/maxVolume ;
int newVolume = (int) ((e1.getY() - e2.getY())/value + oldVolume);
mAudioManager.setStreamVolume(AudioManager.STREAM_MUSIC,newVolume,AudioManager.FLAG_PLAY_SOUND);
//要強行轉(zhuǎn)Float類型才能算出小數(shù)點，不然結(jié)果一直為0
int volumeProgress = (int) (newVolume/Float.valueOf(maxVolume) *100);
if (volumeProgress >= 50){
scl.setImageResource(R.drawable.volume_higher_w);
}else if (volumeProgress > 0){
scl.setImageResource(R.drawable.volume_lower_w);
}else {
scl.setImageResource(R.drawable.volume_off_w);
}
scl.setProgress(volumeProgress);
scl.show();
}
@Override
public void onBrightnessGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
//下面這是設(shè)置當前APP亮度的方法
newBrightness += brightness;
if (newBrightness < 0){
newBrightness = 0;
}else if (newBrightness > 1){
newBrightness = 1;
}
mLayoutParams.screenBrightness = newBrightness;
mWindow.setAttributes(mLayoutParams);
scl.setProgress((int) (newBrightness * 100));
scl.setImageResource(R.drawable.brightness_w);
scl.show();
}
@Override
public void onEndFF_REW(MotionEvent e) {
makeToast("設(shè)置進度為" + newProgress);
}
@Override
public void onFF_REWGesture(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
float offset = e2.getX() - e1.getX();
//根據(jù)移動的正負決定快進還是快退
if (offset > 0) {
scl.setImageResource(R.drawable.ff);
newProgress = (int) (oldProgress + offset/ly_VG.getWidth() * 100);
if (newProgress > 100){
newProgress = 100;
}
}else {
scl.setImageResource(R.drawable.fr);
newProgress = (int) (oldProgress + offset/ly_VG.getWidth() * 100);
if (newProgress < 0){
newProgress = 0;
}
}
scl.setProgress(newProgress);
scl.show();
}
@Override
public void onSingleTapGesture(MotionEvent e) {
makeToast("SingleTap");
}
@Override
public void onDoubleTapGesture(MotionEvent e) {
makeToast("DoubleTap");
}
private void makeToast(String str){
Toast.makeText(this,str,Toast.LENGTH_SHORT).show();
}
//...
這里沒有處理多點觸控，所以實際效果是觸控手指只看第一根，后面落下的手指動作都忽視。
最后貼出調(diào)節(jié)系統(tǒng)亮度的輔助類：
/**
* Author: yanzhikai
* Description: 用于輔助調(diào)節(jié)亮度的類
* Email: yanzhikai_yjk@qq.com
*/
public class BrightnessHelper {
private ContentResolver resolver;
private int maxBrightness = 255;
public BrightnessHelper(Context context){
resolver = context.getContentResolver();
}
/*
* 調(diào)整亮度范圍
*/
private int adjustBrightnessNumber(int brightness){
if (brightness < 0) {
brightness = 0;
} else if (brightness > 255) {
brightness = 255;
}
return brightness;
}
/*
* 關(guān)閉自動調(diào)節(jié)亮度
*/
public void offAutoBrightness(){
try {
if(Settings.System.getInt(resolver, Settings.System.SCREEN_BRIGHTNESS_MODE) == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC)
{
Settings.System.putInt(resolver,
Settings.System.SCREEN_BRIGHTNESS_MODE,
Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);
}
} catch (Settings.SettingNotFoundException e) {
e.printStackTrace();
}
}
/*
* 獲取系統(tǒng)亮度
*/
public int getBrightness(){
return Settings.System.getInt(resolver, Settings.System.SCREEN_BRIGHTNESS, 255);
}
/*
* 設(shè)置系統(tǒng)亮度，如果有設(shè)置了自動調(diào)節(jié)，請先調(diào)用offAutoBrightness()方法關(guān)閉自動調(diào)節(jié)，否則會設(shè)置失敗
*/
public void setSystemBrightness(int newBrightness){
Settings.System.putInt(resolver, Settings.System.SCREEN_BRIGHTNESS
,adjustBrightnessNumber(newBrightness));
}
public int getMaxBrightness() {
return maxBrightness;
}
/*
* 設(shè)置當前APP的亮度
*/
public void setAppBrightness(float brightnessPercent, Activity activity){
Window window = activity.getWindow();
WindowManager.LayoutParams layoutParams = window.getAttributes();
layoutParams.screenBrightness = brightnessPercent;
window.setAttributes(layoutParams);
}
}
上面調(diào)節(jié)亮度選擇的是控制當前APP的亮度，不改變系統(tǒng)亮度。其實這些控制的實現(xiàn)是多種多樣的，我這里只是給出一種封裝GestureDetector的思路和實現(xiàn)方法，各個步驟都說得挺清楚了，具體的細節(jié)大家可以根據(jù)自己的需求改動。
后話
這篇博客是上一篇GestureDetector全面分析的后續(xù)，是GestureDetector的實踐，原本是想合在一起的，結(jié)果發(fā)現(xiàn)太長了。經(jīng)過GestureDetector的洗禮之后，感覺我對Android觸摸事件輸入的處理更加熟悉了，在這里分享出來我的經(jīng)驗，水平有限，如有錯漏，敬請指正。
最后貼一下demo地址，喜歡的可以給個Star！
https://github.com/totond/GestureTest
