我想在我的应用程序中显示动画GIF图像。 我发现Android本身并不支持GIF动画。
但是它可以使用AnimationDrawable显示动画:
开发>指南>图像和图形>绘图概述
这个例子使用动画保存为框架的应用程序资源,但我需要的是直接显示动画gif。
我的计划是将动画GIF分解为帧,并将每帧添加为可绘制的AnimationDrawable。
有人知道如何从动画GIF中提取帧并将它们转换为可绘制的吗?
我想在我的应用程序中显示动画GIF图像。 我发现Android本身并不支持GIF动画。
但是它可以使用AnimationDrawable显示动画:
开发>指南>图像和图形>绘图概述
这个例子使用动画保存为框架的应用程序资源,但我需要的是直接显示动画gif。
我的计划是将动画GIF分解为帧,并将每帧添加为可绘制的AnimationDrawable。
有人知道如何从动画GIF中提取帧并将它们转换为可绘制的吗?
当前回答
直接从URL到应用程序布局显示动画GIF的简单方法是使用WebView类。
步骤1: 在XML布局中
< WebView android: id =“@ + id / webView” android: layout_width = " 50 dp” android: layout_height = " 50 dp” />
第二步:在活动中
网络视图 wb; wb = (WebView) findViewById(R.id.webView); wb.loadUrl(“https://.......);
步骤3:在Manifest.XML中设置Internet权限
< uses-permission android: name = " android.permission。互联网" / >
步骤4:如果你想让你的GIF背景透明,让GIF适合你的布局
wb.setBackgroundColor (Color.TRANSPARENT); wb.getSettings () .setLoadWithOverviewMode(真正的); wb.getSettings () .setUseWideViewPort(真正的);
其他回答
也放(main/assets/ htmlls /name.gif)[用这个HTML调整大小]
<html style="margin: 0;">
<body style="margin: 0;">
<img src="name.gif" style="width: 100%; height: 100%" />
</body>
</html>
在你的Xml中像这样声明(main/res/layout/name.xml):[你定义大小,例如]
<WebView
android:layout_width="70dp"
android:layout_height="70dp"
android:id="@+id/webView"
android:layout_gravity="center_horizontal" />
在你的活动中,把下一个代码放在onCreate里面
web = (WebView) findViewById(R.id.webView);
web.setBackgroundColor(Color.TRANSPARENT); //for gif without background
web.loadUrl("file:///android_asset/htmls/name.html");
如果你想动态加载,你必须用数据加载webview:
// or "[path]/name.gif" (e.g: file:///android_asset/name.gif for resources in asset folder), and in loadDataWithBaseURL(), you don't need to set base URL, on the other hand, it's similar to loadData() method.
String gifName = "name.gif";
String yourData = "<html style=\"margin: 0;\">\n" +
" <body style=\"margin: 0;\">\n" +
" <img src=" + gifName + " style=\"width: 100%; height: 100%\" />\n" +
" </body>\n" +
" </html>";
// Important to add this attribute to webView to get resource from outside.
webView.getSettings().setAllowFileAccess(true);
// Notice: should use loadDataWithBaseURL. BaseUrl could be the base url such as the path to asset folder, or SDCard or any other path, where your images or the other media resides related to your html
webView.loadDataWithBaseURL("file:///android_asset/", yourData, "text/html", "utf-8", null);
// Or if you want to load image from SD card or where else, here is the idea.
String base = Environment.getExternalStorageDirectory().getAbsolutePath().toString();
webView.loadDataWithBaseURL(base + '/', yourData, "text/html", "utf-8", null);
建议:最好是加载gif与静态图像的更多信息,请检查https://developer.android.com/reference/android/graphics/drawable/AnimationDrawable.html
就是这样,我希望你能帮助我。
目前我们可以使用Glide https://github.com/bumptech/glide
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());
}
}
}
}
@PointerNull给出了很好的解决方案,但并不完美。它不能在一些大文件的设备上工作,并显示有bug的Gif动画与前ICS版本的delta帧。 我找到了没有这个bug的解决方案。它是带有原生解码到可绘制的库:koral的android-gif-drawable。
我已经成功地使用了本文中提出的解决方案,一个名为GifMovieView的类,它呈现一个视图,然后可以显示或添加到特定的ViewGroup中。查看指定文章的第2部分和第3部分中介绍的其他方法。
这种方法的唯一缺点是电影上的反锯齿不是很好(一定是使用“阴暗的”Android电影类的副作用)。然后你最好在你的动画GIF中设置一个纯色的背景。
我解决了这个问题,在将gif动画保存到手机之前将其分割成帧,这样我就不必在Android中处理它了。
然后我把每一帧下载到手机上,从中创建Drawable,然后创建AnimationDrawable -非常类似于我的问题中的例子