转载请注明：
http://blog.csdn.net/u012975705/article/details/48717391
在看这篇博文之前对attr自定义属性还是不是很熟的童鞋可以先看看：Android中attr详解（http://blog.csdn.net/u012975705/article/details/48716797）
源码下载：https://github.com/noyo/GifTest
效果图
显示的事两张动态gif图
实现代码
1、布局activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:gif="http://schemas.android.com/apk/res-auto"
android:gravity="center"
android:orientation="vertical" >
<com.practice.noyet.giftest.MyGiftView
android:id="@+id/gif1"
gif:gif="@raw/gift1"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_gravity="center_horizontal"
android:enabled="false" />
<com.practice.noyet.giftest.MyGiftView
android:layout_marginTop="10dp"
gif:gif="@raw/gift2"
android:id="@+id/gif2"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_gravity="center_horizontal"
android:enabled="false" />
</LinearLayout>2、自定义的com.practice.noyet.giftest.MyGiftView.Java代码（代码中都有注释，我就不废话了）：
package com.practice.noyet.giftest;
import android.annotation.SuppressLint;
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;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
/**
* Created by noyet on 2015/9/24.
*/
public class MyGiftView extends View {
/** gift动态效果总时长，在未设置时长时默认为1秒 */
private static final int DEFAULT_MOVIE_DURATION = 1000;
/** gift图片资源ID */
private int mGiftId;
/** Movie实例，用来显示gift图片 */
private Movie mMovie;
/** 显示gift图片的动态效果的开始时间 */
private long mMovieStart;
/** 动态图当前显示第几帧 */
private int mCurrentAnimationTime = 0;
/** 图片离屏幕左边的距离 */
private float mLeft;
/** 图片离屏幕上边的距离 */
private float mTop;
/** 图片的缩放比例 */
private float mScale;
/** 图片在屏幕上显示的宽度 */
private int mMeasuredMovieWidth;
/** 图片在屏幕上显示的高度 */
private int mMeasuredMovieHeight;
/** 是否显示动画,为true表示显示，false表示不显示 */
private boolean mVisible = true;
/** 动画效果是否被暂停 */
private volatile boolean mPaused = false;
public MyGiftView(Context context) {
this(context, null);
}
public MyGiftView(Context context, AttributeSet attrs) {
this(context, attrs, R.styleable.CustomTheme_gifViewStyle);
}
public MyGiftView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
setViewAttributes(context, attrs, defStyleAttr);
}
/**
*
* @param context 上下文
* @param attrs 自定义属性
* @param defStyle 默认风格
*/
@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);
}
final TypedArray array = context.obtainStyledAttributes(attrs,
R.styleable.MyGiftView, defStyle, R.style.Widget_MyGiftView);
mGiftId = array.getResourceId(R.styleable.MyGiftView_gif, -1);
mPaused = array.getBoolean(R.styleable.MyGiftView_paused, false);
array.recycle();
if (mGiftId != -1) {
byte[] bytes = getGiftBytes();
mMovie = Movie.decodeByteArray(bytes, 0, bytes.length);
}
}
/**
* 设置gif图资源
* @param giftResId
*/
public void setMovieResource(int giftResId) {
this.mGiftId = giftResId;
byte[] bytes = getGiftBytes();
mMovie = Movie.decodeByteArray(bytes, 0, bytes.length);
requestLayout();
}
/**
* 手动设置 Movie对象
* @param movie Movie
*/
public void setMovie(Movie movie) {
this.mMovie = movie;
requestLayout();
}
/**
* 得到Movie对象
* @return Movie
*/
public Movie getMovie() {
return mMovie;
}
/**
* 设置要显示第几帧动画
* @param time
*/
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);
}
}
}
/**
* 重绘
*/
@SuppressLint("NewApi")
private void invalidateView() {
if (mVisible) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
postInvalidateOnAnimation();
} else {
invalidate();
}
}
}
/**
* 更新当前显示进度
*/
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);
}
/**
* 绘制图片
* @param canvas 画布
*/
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();
}
/**
* 将gif图片转换成byte[]
* @return byte[]
*/
private byte[] getGiftBytes() {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
InputStream is = getResources().openRawResource(mGiftId);
byte[] b = new byte[1024];
int len;
try {
while ((len = is.read(b, 0, 1024)) != -1) {
baos.write(b, 0, len);
}
baos.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return baos.toByteArray();
}
}
3、MainActivity.java：
package com.practice.noyet.giftest;
import android.app.Activity;
import android.os.Bundle;
public class MainActivity extends Activity {
private MyGiftView gif1;
private MyGiftView gif2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gif1 = (MyGiftView) findViewById(R.id.gif1);
gif2 = (MyGiftView) findViewById(R.id.gif2);
/** ........ */
}
}
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