我想在我的应用程序中显示动画GIF图像。但很遗憾,Android不支持原生的动画GIF。
不过,Android可以使用AnimationDrawable来显示动画:
示例使用应用程序资源中保存为帧的动画,但我需要直接显示动画GIF。
我的计划是将动画GIF拆分为帧并将每个帧作为drawable添加到AnimationDrawable中。
有人知道如何从动画GIF中提取帧,并将每个帧转换为Drawable吗?
我想在我的应用程序中显示动画GIF图像。但很遗憾,Android不支持原生的动画GIF。
不过,Android可以使用AnimationDrawable来显示动画:
示例使用应用程序资源中保存为帧的动画,但我需要直接显示动画GIF。
我的计划是将动画GIF拆分为帧并将每个帧作为drawable添加到AnimationDrawable中。
有人知道如何从动画GIF中提取帧,并将每个帧转换为Drawable吗?
最简单的方法 - 可以考虑下面的代码
我们可以利用ImageView setImageResource,参考下面的代码。
如果您有gif的多个分割图像,则可以使用下面的代码来显示图像。只需从在线工具中将gif拆分为单个png,并按以下顺序将图像放入drawable中
image_1.png,image_2.png等。
具有处理程序以动态更改图像。
int imagePosition = 1;
Handler handler = new Handler();
Runnable runnable = new Runnable() {
public void run() {
updateImage();
}
};
public void updateImage() {
appInstance.runOnUiThread(new Runnable() {
@Override
public void run() {
int resId = getResources().getIdentifier("image_" + imagePosition, "drawable", appInstance.getPackageName());
gifImageViewDummy.setImageResource(resId);
imagePosition++;
//Consider you have 30 image for the anim
if (imagePosition == 30) {
//this make animation play only once
handler.removeCallbacks(runnable);
} else {
//You can define your own time based on the animation
handler.postDelayed(runnable, 50);
}
//to make animation to continue use below code and remove above if else
// if (imagePosition == 30)
//imagePosition = 1;
// handler.postDelayed(runnable, 50);
//
}
});
}
在您的应用程序布局中直接从URL显示动画GIF的简单方法是使用WebView类。
步骤1: 在您的布局XML中
<WebView
android:id="@+id/webView"
android:layout_width="50dp"
android:layout_height="50dp"
/>
WebView wb;
wb = (WebView) findViewById(R.id.webView);
wb.loadUrl("https://.......);
<uses-permission android:name="android.permission.INTERNET" />
步骤4: 如果您想要将GIF背景设置为透明,并使其适应您的布局
wb.setBackgroundColor(Color.TRANSPARENT);
wb.getSettings().setLoadWithOverviewMode(true);
wb.getSettings().setUseWideViewPort(true);
这是我为在应用程序中展示 GIF 做出的一些工作。我扩展了 ImageView,使人们可以自由使用它的属性。它可以从 URL 或从资产目录中显示 GIF。 此库还可轻松扩展类以继承它,并扩展其支持不同方法来初始化 GIF。
https://github.com/Gavras/GIFView
Github页面上有一个小指南。
它也被发布在Android Arsenal上:
https://android-arsenal.com/details/1/4947
使用示例:
从 XML 中:
<com.whygraphics.gifview.gif.GIFView xmlns:gif_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/main_activity_gif_vie"
android:layout_width="200dp"
android:layout_height="200dp"
android:scaleType="center"
gif_view:gif_src="url:http://pop.h-cdn.co/assets/16/33/480x264/gallery-1471381857-gif-season-2.gif" />
在这个活动中:
GIFView mGifView = (GIFView) findViewById(R.id.main_activity_gif_vie);
mGifView.setOnSettingGifListener(new GIFView.OnSettingGifListener() {
@Override
public void onSuccess(GIFView view, Exception e) {
Toast.makeText(MainActivity.this, "onSuccess()", Toast.LENGTH_SHORT).show();
}
@Override
public void onFailure(GIFView view, Exception e) {
}
});
通过编程设置gif:
mGifView.setGifResource("asset:gif1");
Glide.with(this)
.asGif()
.load(R.raw.onboarding_layers) //Your gif resource
.apply(RequestOptions.diskCacheStrategyOf(DiskCacheStrategy.NONE))
.listener(new RequestListener<GifDrawable>() {
@Override
public boolean onLoadFailed(@Nullable @org.jetbrains.annotations.Nullable GlideException e, Object model, Target<GifDrawable> target, boolean isFirstResource) {
return false;
}
@Override
public boolean onResourceReady(GifDrawable resource, Object model, Target<GifDrawable> target, DataSource dataSource, boolean isFirstResource) {
resource.setLoopCount(1);
return false;
}
})
.into((ImageView) view.findViewById(R.id.layer_icons));
public class Test extends GraphicsActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
private Bitmap mBitmap;
private Bitmap mBitmap2;
private Bitmap mBitmap3;
private Bitmap mBitmap4;
private Drawable mDrawable;
private Movie mMovie;
private long mMovieStart;
// Set to false to use decodeByteArray
private static final boolean DECODE_STREAM = true;
private static byte[] streamToBytes(InputStream is) {
ByteArrayOutputStream os = new ByteArrayOutputStream(1024);
byte[] buffer = new byte[1024];
int len;
try {
while ((len = is.read(buffer)) >= 0) {
os.write(buffer, 0, len);
}
} catch (java.io.IOException e) {
}
return os.toByteArray();
}
public SampleView(Context context) {
super(context);
setFocusable(true);
java.io.InputStream is;
is = context.getResources().openRawResource(R.drawable.icon);
BitmapFactory.Options opts = new BitmapFactory.Options();
Bitmap bm;
opts.inJustDecodeBounds = true;
bm = BitmapFactory.decodeStream(is, null, opts);
// now opts.outWidth and opts.outHeight are the dimension of the
// bitmap, even though bm is null
opts.inJustDecodeBounds = false; // this will request the bm
opts.inSampleSize = 4; // scaled down by 4
bm = BitmapFactory.decodeStream(is, null, opts);
mBitmap = bm;
// decode an image with transparency
is = context.getResources().openRawResource(R.drawable.icon);
mBitmap2 = BitmapFactory.decodeStream(is);
// create a deep copy of it using getPixels() into different configs
int w = mBitmap2.getWidth();
int h = mBitmap2.getHeight();
int[] pixels = new int[w * h];
mBitmap2.getPixels(pixels, 0, w, 0, 0, w, h);
mBitmap3 = Bitmap.createBitmap(pixels, 0, w, w, h,
Bitmap.Config.ARGB_8888);
mBitmap4 = Bitmap.createBitmap(pixels, 0, w, w, h,
Bitmap.Config.ARGB_4444);
mDrawable = context.getResources().getDrawable(R.drawable.icon);
mDrawable.setBounds(150, 20, 300, 100);
is = context.getResources().openRawResource(R.drawable.animated_gif);
if (DECODE_STREAM) {
mMovie = Movie.decodeStream(is);
} else {
byte[] array = streamToBytes(is);
mMovie = Movie.decodeByteArray(array, 0, array.length);
}
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(0xFFCCCCCC);
Paint p = new Paint();
p.setAntiAlias(true);
canvas.drawBitmap(mBitmap, 10, 10, null);
canvas.drawBitmap(mBitmap2, 10, 170, null);
canvas.drawBitmap(mBitmap3, 110, 170, null);
canvas.drawBitmap(mBitmap4, 210, 170, null);
mDrawable.draw(canvas);
long now = android.os.SystemClock.uptimeMillis();
if (mMovieStart == 0) { // first time
mMovieStart = now;
}
if (mMovie != null) {
int dur = mMovie.duration();
if (dur == 0) {
dur = 1000;
}
int relTime = (int) ((now - mMovieStart) % dur);
mMovie.setTime(relTime);
mMovie.draw(canvas, getWidth() - mMovie.width(), getHeight()
- mMovie.height());
invalidate();
}
}
}
}
class GraphicsActivity extends Activity {
// set to true to test Picture
private static final boolean TEST_PICTURE = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public void setContentView(View view) {
if (TEST_PICTURE) {
ViewGroup vg = new PictureLayout(this);
vg.addView(view);
view = vg;
}
super.setContentView(view);
}
}
class PictureLayout extends ViewGroup {
private final Picture mPicture = new Picture();
public PictureLayout(Context context) {
super(context);
}
public PictureLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public void addView(View child) {
if (getChildCount() > 1) {
throw new IllegalStateException(
"PictureLayout can host only one direct child");
}
super.addView(child);
}
@Override
public void addView(View child, int index) {
if (getChildCount() > 1) {
throw new IllegalStateException(
"PictureLayout can host only one direct child");
}
super.addView(child, index);
}
@Override
public void addView(View child, LayoutParams params) {
if (getChildCount() > 1) {
throw new IllegalStateException(
"PictureLayout can host only one direct child");
}
super.addView(child, params);
}
@Override
public void addView(View child, int index, LayoutParams params) {
if (getChildCount() > 1) {
throw new IllegalStateException(
"PictureLayout can host only one direct child");
}
super.addView(child, index, params);
}
@Override
protected LayoutParams generateDefaultLayoutParams() {
return new LayoutParams(LayoutParams.MATCH_PARENT,
LayoutParams.MATCH_PARENT);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
final int count = getChildCount();
int maxHeight = 0;
int maxWidth = 0;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() != GONE) {
measureChild(child, widthMeasureSpec, heightMeasureSpec);
}
}
maxWidth += getPaddingLeft() + getPaddingRight();
maxHeight += getPaddingTop() + getPaddingBottom();
Drawable drawable = getBackground();
if (drawable != null) {
maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
}
setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec),
resolveSize(maxHeight, heightMeasureSpec));
}
private void drawPict(Canvas canvas, int x, int y, int w, int h, float sx,
float sy) {
canvas.save();
canvas.translate(x, y);
canvas.clipRect(0, 0, w, h);
canvas.scale(0.5f, 0.5f);
canvas.scale(sx, sy, w, h);
canvas.drawPicture(mPicture);
canvas.restore();
}
@Override
protected void dispatchDraw(Canvas canvas) {
super.dispatchDraw(mPicture.beginRecording(getWidth(), getHeight()));
mPicture.endRecording();
int x = getWidth() / 2;
int y = getHeight() / 2;
if (false) {
canvas.drawPicture(mPicture);
} else {
drawPict(canvas, 0, 0, x, y, 1, 1);
drawPict(canvas, x, 0, x, y, -1, 1);
drawPict(canvas, 0, y, x, y, 1, -1);
drawPict(canvas, x, y, x, y, -1, -1);
}
}
@Override
public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
location[0] = getLeft();
location[1] = getTop();
dirty.set(0, 0, getWidth(), getHeight());
return getParent();
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
final int count = super.getChildCount();
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() != GONE) {
final int childLeft = getPaddingLeft();
final int childTop = getPaddingTop();
child.layout(childLeft, childTop,
childLeft + child.getMeasuredWidth(),
childTop + child.getMeasuredHeight());
}
}
}
}