Android 显示Gif 动态图片

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import android.widget.Button;

public class Main extends ActionBarActivity {

private GifImageView gifImageView;

private Button btnPause;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

gifImageView = (GifImageView) findViewById(R.id.imgGif);

gifImageView.setMovieResource(R.raw.showme);

btnPause = (Button) findViewById(R.id.btnPause);

btnPause.setOnClickListener(new OnClickListenerImp());

}

private class OnClickListenerImp implements View.OnClickListener {

@Override

public void onClick(View v) {

if (v == btnPause) {

if (gifImageView.isPaused()) {

gifImageView.setPaused(false);

btnPause.setText("Pause");

} else {

gifImageView.setPaused(true);

btnPause.setText("Play");

}

}

}

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

getMenuInflater().inflate(R.menu.main, menu);

return true;

}

@Override

public boolean onOptionsItemSelected(MenuItem item) {

int id = item.getItemId();

if (id == R.id.action_settings) {

return true;

}

return super.onOptionsItemSelected(item);

}

}

核心的自定义View:

package com.zms.showgif;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Canvas;

import android.graphics.Movie;

import android.os.Build;

import android.util.AttributeSet;

import android.view.View;

/**

  • Created by AlexZhou on 2015/1/29.

  • 16:42

*/

public class GifImageView 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 GifImageView(Context context) {

this(context, null);

}

public GifImageView(Context context, AttributeSet attrs) {

this(context, attrs, R.styleable.Gif_style);

}

public GifImageView(Context context, AttributeSet attrs, int defStyle) {

super(context, attrs, defStyle);

setViewAttributes(context, attrs, defStyle);

}

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.Gif, defStyle, -1);

mMovieResourceId = array.getResourceId(R.styleable.Gif_resource, -1);

mPaused = array.getBoolean(R.styleable.Gif_paused, false);

array.recycle();

if (mMovieResourceId != -1) {

mMovie = Movie.decodeStream(getResources().openRawResource(

mMovieResourceId));

}

}

public int setMovieResource(int movieResId) {

this.mMovieResourceId = movieResId;

mMovie = Movie.decodeStream(getResources().openRawResource(

mMovieResourceId));

requestLayout();

return movieResId;

}

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 {

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