我想为Android创建一个进度条.我的方形进度条有四个图像.
我正在使用android定义的进度条:
但是,如果我想制作一个正方形而不是圆形,我该怎么办呢?如何将4张图像传递到进度条?
例:
通常你有2个选择:
1.如前所述,使用animation-list
和交换图片.
这个可能是更简单的解决方案,因为它们可以通过AnimationDrawable相对容易地进行动画处理.唯一的缺点是您需要至少16张图像(在所有分辨率下)用于您的给定结果.
2.使用自定义drawable.
这是更复杂的方法.您将不得不自己进行绘图和动画制作,对于大多数没有良好文档的人来说,这是一项艰巨的任务.
因此,您必须extends Drawable implements Runnable, Animatable
提供一些好的实现.
以下是基本的实现,计算一次位置,然后绘制它们.动画(各个圆圈的大小)可以而且应该进一步调整;)
结果有3种变体:
public class RectProgressDrawable extends Drawable implements Runnable, Animatable { private static final long FRAME_DELAY = 1000 / 60; private static final String TAG = "RectProgressDrawable"; private boolean mRunning = false; private long mStartTime; private int mDuration = 1000; private Paint mPaint; private float[] posX; private float[] posY; private float mSize; private int mPoints = 5; /** * The padding in px. */ private int mPadding = 4; private int mAnimatedPoints = 5; public void setPoints(int points) { if (points != mPoints) { mPoints = points; init(); } } private void init() { if (mPaint == null) { mPaint = new Paint(); mPaint.setColor(Color.WHITE); mPaint.setAntiAlias(true); mPaint.setStyle(Paint.Style.FILL); } posX = new float[(mPoints - 1) * 4]; posY = new float[(mPoints - 1) * 4]; Rect bounds = new Rect(); bounds.set(getBounds()); bounds.inset(mPadding, mPadding); float cellWidth = ((float) bounds.width()) / ((float) mPoints); float cellHeight = ((float) bounds.height()) / ((float) mPoints); float min = Math.min(cellWidth, cellHeight); mSize = min / (mPoints - 1); for (int i = 0; i < mPoints; i++) { // top row posX[i] = bounds.left + cellWidth * (float) i + cellWidth / 2; posY[i] = bounds.top + cellHeight / 2; } for (int i = 0; i < mPoints - 2; i++) { // sides // right side top bottom posX[mPoints + i] = bounds.left + cellWidth * (mPoints - 1) + cellWidth / 2; posY[mPoints + i] = bounds.top + cellHeight * (i + 1) + cellHeight / 2; //left side bottom top posX[3 * mPoints - 2 + i] = bounds.left + cellWidth / 2; posY[3 * mPoints - 2 + i] = bounds.top + cellHeight * (mPoints - 2 - i) + cellHeight / 2; } for (int i = 0; i < mPoints; i++) { // bottom from right to left posX[2 * mPoints - 2 + i] = bounds.left + cellWidth * (mPoints - 1 - i) + cellWidth / 2; posY[2 * mPoints - 2 + i] = bounds.top + cellHeight * (mPoints - 1) + cellHeight / 2; } } @Override public void draw(Canvas canvas) { if (isRunning()) { // animation in progress final int save = canvas.save(); long timeDiff = SystemClock.uptimeMillis() - mStartTime; float progress = ((float) timeDiff) / ((float) mDuration); // 0..1 int level = ((int) (progress * posX.length)) % posX.length; // current value 0..posX.length for (int i = 0; i < posX.length; i++) { if ((i >= level && i < level + mAnimatedPoints) || level + mAnimatedPoints > posX.length && i < (level + mAnimatedPoints) % posX.length) { float num = (i - level + posX.length) % posX.length; // 0..5 float size = mSize * (1 + (num * (1f / mAnimatedPoints))); float sizeNext = mSize * (1 + ((num + 1) * (1f / mAnimatedPoints))); float levelProgress = progress * posX.length - (int) (progress * posX.length); float currentSize; if (num == (mAnimatedPoints - 1)) { // grow to next size currentSize = mSize + (size - mSize) * levelProgress; } else { // shrink currentSize = size + (sizeNext - size) * (1 - levelProgress); } canvas.drawCircle(posX[i], posY[i], currentSize, mPaint); } else { canvas.drawCircle(posX[i], posY[i], mSize, mPaint); } } canvas.restoreToCount(save); } else { // draw normal for (int i = 0; i < posX.length; i++) { canvas.drawCircle(posX[i], posY[i], mSize, mPaint); } } } @Override public void setBounds(int left, int top, int right, int bottom) { super.setBounds(left, top, right, bottom); init(); } @Override public void setAlpha(int alpha) { } @Override public void setColorFilter(ColorFilter colorFilter) { } @Override public int getOpacity() { return 0; } @Override public void start() { if (mRunning) stop(); mRunning = true; mStartTime = SystemClock.uptimeMillis(); invalidateSelf(); scheduleSelf(this, SystemClock.uptimeMillis() + FRAME_DELAY); } @Override public void stop() { unscheduleSelf(this); mRunning = false; } @Override public boolean isRunning() { return mRunning; } @Override public void run() { invalidateSelf(); long uptimeMillis = SystemClock.uptimeMillis(); if (uptimeMillis + FRAME_DELAY < mStartTime + mDuration) { scheduleSelf(this, uptimeMillis + FRAME_DELAY); } else { mRunning = false; start(); } } public void setAnimatedPoints(int animatedPoints) { mAnimatedPoints = animatedPoints; } }
使用
ProgressBar progressBar = (ProgressBar) findViewById(R.id.progress); progressBar.setIndeterminateDrawable(new RectProgressDrawable()); progressBar.setIndeterminate(true);
或者,您可以在此处查看工作项目中的完整源代码
我正在用一堆图像来做这件事animation-list
:
而且res\drawable\loading_progres_indicator_animation.xml
:
- .....
每个loading_progress_indicator_XX
图像都是进度状态指示器.
带指示符的自定义视图:
public final class LoadingAnimationView extends FrameLayout { ImageView loadingAnimationImageView; AnimationDrawable loadingProgressAnimation; Handler handler = new Handler(Looper.getMainLooper()); public LoadingAnimationView(Context context) { super(context); initialize(); } private void initialize() { LayoutInflater.from(getContext()).inflate(R.layout.view_loading_videoview, this); loadingAnimationImageView = (ImageView)getView().findViewById(R.id.loadingAnimationImageView); loadingProgressAnimation = (AnimationDrawable) loadingAnimationImageView.getBackground(); adaptToVisibility(getVisibility()); } @Override public void setVisibility(int visibility) { super.setVisibility(visibility); adaptToVisibility(visibility); } void adaptToVisibility(final int visibility) { if (visibility == VISIBLE) { loadingProgressAnimation.start(); //This is to avoid "blinking" of progress indicator (if page is loading from cache) handler.postDelayed(new Runnable() { @Override public void run() { loadingAnimationImageView.setVisibility(visibility); } }, 200); } else { loadingProgressAnimation.stop(); loadingAnimationImageView.setVisibility(visibility); } } }
因此,在我的情况下,它看起来像:
因此,您需要的只是指标和自定义视图的状态,如上所示.
要获取指标的状态,您可以转换gif
为png
我建议使用EzGif服务的列表:
另一种选择 - 您可以重复使用加载指示器的几十个自定义实现中的一个(如果它有一些足够接近您的指示符)或这个(尽管,大多数开源指标是循环的).
我希望它有所帮助.