Android显示GIF图片实例代码
最近.一个朋友跟我说想,我给她弄个闹钟APP软件...功能其实很简单...只需要弄个简单的闹钟.自己设计设计时间.然后时间到了的时候,闹铃放的声音是男朋友录制好的声音...于是就开始整了....
第一次做这种的时候.我想把首页界面做成一个GIF动画特效的.这样看起来可爱点...适合妹子用,于是就有了下面这个效果图
上代码
ndroid中的Android.graphics.Movie 这个类,这是android提供给我们的一个非常方便的工具。
首先,重写控件View,自定义一个展示gif图的GifView
Movie其实管理着GIF动画中的多个帧,只需要通过 setTime() 一下就可以让它在draw()的时候绘出相应的那帧图像。通过当前时间与duration之间的换算关系,是很容易实现GIF动起来的效果。
public class GifView extends View { /** * 默认为1秒 */ private static final int DEFAULT_MOVIE_DURATION = 1000; private int mMovieResourceId; private Movie mMovie; private long mMovieStart; private int mCurrentAnimationTime = 0; private float mLeft; private float mTop; private float mScale; private int mMeasuredMovieWidth; private int mMeasuredMovieHeight; private boolean mVisible = true; private volatile boolean mPaused = false; public GifView(Context context) { this(context, null); } public GifView(Context context, AttributeSet attrs) { this(context, attrs, R.styleable.CustomTheme_gifViewStyle); } public GifView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setViewAttributes(context, attrs, defStyle); } @SuppressLint("NewApi") private void setViewAttributes(Context context, AttributeSet attrs, int defStyle) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { setLayerType(View.LAYER_TYPE_SOFTWARE, null); } // 从描述文件中读出gif的值,创建出Movie实例 final TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.GifView, defStyle, R.style.Widget_GifView); mMovieResourceId = array.getResourceId(R.styleable.GifView_gif, -1); mPaused = array.getBoolean(R.styleable.GifView_paused, false); array.recycle(); if (mMovieResourceId != -1) { mMovie = Movie.decodeStream(getResources().openRawResource( mMovieResourceId)); } } /** * 设置gif图资源 * * @param movieResId */ public void setMovieResource(int movieResId) { this.mMovieResourceId = movieResId; mMovie = Movie.decodeStream(getResources().openRawResource( mMovieResourceId)); requestLayout(); } public void setMovie(Movie movie) { this.mMovie = movie; requestLayout(); } public Movie getMovie() { return mMovie; } public void setMovieTime(int time) { mCurrentAnimationTime = time; invalidate(); } /** * 设置暂停 * * @param paused */ public void setPaused(boolean paused) { this.mPaused = paused; if (!paused) { mMovieStart = android.os.SystemClock.uptimeMillis() - mCurrentAnimationTime; } invalidate(); } /** * 判断gif图是否停止了 * * @return */ public boolean isPaused() { return this.mPaused; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if (mMovie != null) { int movieWidth = mMovie.width(); int movieHeight = mMovie.height(); int maximumWidth = MeasureSpec.getSize(widthMeasureSpec); float scaleW = (float) movieWidth / (float) maximumWidth; mScale = 1f / scaleW; mMeasuredMovieWidth = maximumWidth; mMeasuredMovieHeight = (int) (movieHeight * mScale); setMeasuredDimension(mMeasuredMovieWidth, mMeasuredMovieHeight); } else { setMeasuredDimension(getSuggestedMinimumWidth(), getSuggestedMinimumHeight()); } } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { super.onLayout(changed, l, t, r, b); mLeft = (getWidth() - mMeasuredMovieWidth) / 2f; mTop = (getHeight() - mMeasuredMovieHeight) / 2f; mVisible = getVisibility() == View.VISIBLE; } @Override protected void onDraw(Canvas canvas) { if (mMovie != null) { if (!mPaused) { updateAnimationTime(); drawMovieFrame(canvas); invalidateView(); } else { drawMovieFrame(canvas); } } } @SuppressLint("NewApi") private void invalidateView() { if (mVisible) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { invalidate(); } } } private void updateAnimationTime() { long now = android.os.SystemClock.uptimeMillis(); // 如果第一帧,记录起始时间 if (mMovieStart == 0) { mMovieStart = now; } // 取出动画的时长 int dur = mMovie.duration(); if (dur == 0) { dur = DEFAULT_MOVIE_DURATION; } // 算出需要显示第几帧 mCurrentAnimationTime = (int) ((now - mMovieStart) % dur); } private void drawMovieFrame(Canvas canvas) { // 设置要显示的帧,绘制即可 mMovie.setTime(mCurrentAnimationTime); canvas.save(Canvas.MATRIX_SAVE_FLAG); canvas.scale(mScale, mScale); mMovie.draw(canvas, mLeft / mScale, mTop / mScale); canvas.restore(); } @SuppressLint("NewApi") @Override public void onScreenStateChanged(int screenState) { super.onScreenStateChanged(screenState); mVisible = screenState == SCREEN_STATE_ON; invalidateView(); } @SuppressLint("NewApi") @Override protected void onVisibilityChanged(View changedView, int visibility) { super.onVisibilityChanged(changedView, visibility); mVisible = visibility == View.VISIBLE; invalidateView(); } @Override protected void onWindowVisibilityChanged(int visibility) { super.onWindowVisibilityChanged(visibility); mVisible = visibility == View.VISIBLE; invalidateView(); } }
其次,在xml布局文件中,把这个view定义进去,代码如下:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#ffffff" android:gravity="center" android:orientation="vertical" > <com.example.alarmtest.GifView android:id="@+id/gif1" android:layout_width="300dp" android:layout_height="300dp" android:layout_gravity="center_horizontal" android:enabled="false"/> <Button android:id="@+id/bu" android:text="进入" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal"/> </LinearLayout>
最后,在MainActivity中的使用,代码如下:
public class FirstActivity extends Activity { private GifView gif; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_first); gif = (GifView) findViewById(R.id.gif1); // 设置背景gif图片资源 gif.setMovieResource(R.raw.a123); } }
Styles.xml
<declare-styleable name="GifView"> <attr name="gif" format="reference" /> <attr name="paused" format="boolean" /> </declare-styleable> <declare-styleable name="CustomTheme"> <attr name="gifViewStyle" format="reference" /> </declare-styleable> <style name="Widget_GifView"></style>
raw是res下面的一个文件放的是GIF动画图噢
我这里放了一个动画图 跟一个 音乐文件,因为我要做的是一个有声音的闹铃
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