2022 |
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2022
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一、运行效果图如下，背景图可以上下左右四个方向滚动。
二、直接上源码。 1、
2、src\main\java\com\giada\healthcode\MainActivity.java package com.giada.healthcode; import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.view.WindowManager; import android.widget.Button; import android.widget.TextView; public class MainActivity extends AppCompatActivity { private Button btn_start,btn_stop,btn_change,btn_speedup; private SrcScrollFrameLayout fl_main; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS); setContentView(R.layout.activity_main); btn_start = (Button) findViewById(R.id.btn_start); btn_stop = (Button) findViewById(R.id.btn_stop); btn_change = (Button) findViewById(R.id.btn_change); btn_speedup = (Button) findViewById(R.id.btn_speedup); fl_main = (SrcScrollFrameLayout) findViewById(R.id.fl_main); btn_start.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { fl_main.startScroll(); fl_main.DEFAULT_DRAW_INTERVALS_TIME=10; } }); btn_stop.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { fl_main.stopScroll(); } }); btn_change.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { fl_main.changeScrollOrientation(); } }); btn_speedup.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { fl_main.DEFAULT_DRAW_INTERVALS_TIME -= 10; } }); } }3、src\main\java\com\giada\healthcode\SrcScrollFrameLayout.java 核心代码 package com.giada.healthcode; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Bitmap; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.util.AttributeSet; import android.widget.FrameLayout; import androidx.annotation.ColorInt; import androidx.annotation.IntDef; import androidx.annotation.NonNull; import androidx.annotation.Nullable; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; /** * PackageName : com.ziwenl.library.widgets * Author : Ziwen Lan * Date : 2020/5/13 * Time : 11:23 * Introduction :仿小红书登陆页面背景图无限滚动 FrameLayout * 功能特点： * 1.将选择的图片按比例缩放填满当前 View 高度 * 2.背景图片缩放后宽/高度小于当前 View 宽/高度时自动复制黏贴直到占满当前 View 宽/高度，以此来达到无限滚动效果 * 3.可通过自定义属性 speed 调整滚动速度，提供 slow、ordinary 和 fast 选项，也可自行填入 int 值，值越大滚动速度越快，建议 1 ≤ speed ≤ 50 * 4.可通过自定义属性 maskLayerColor 设置遮罩层颜色，建议带透明度 * 5.提供 startScroll 和 stopScroll 方法控制开始/停止滚动 * 6.可通过自定义属性 scrollOrientation 设置滚动方向，可设置为上移、下移、左移或右移 * * @Deprecated 建议使用最新的 kotlin 版 {@link SrcLoopScrollFrameLayout}，后续 Java 版本可能将放弃维护 */ @Deprecated public class SrcScrollFrameLayout extends FrameLayout { /** * 滚动方向 * 0:往上滚出 * 1:往下滚出 * 2:往左滚出 * 3:往右滚出 */ public final static int OUT_SLIDE_TOP = 0; public final static int OUT_SLIDE_BOTTOM = 1; public final static int OUT_SLIDE_LEFT = 2; public final static int OUT_SLIDE_RIGHT = 3; @IntDef({OUT_SLIDE_TOP, OUT_SLIDE_BOTTOM, OUT_SLIDE_LEFT, OUT_SLIDE_RIGHT}) @Retention(RetentionPolicy.SOURCE) public @interface ScrollOrientation { } /** * 重绘间隔时间 */ //private final static long DEFAULT_DRAW_INTERVALS_TIME = 5L; public long DEFAULT_DRAW_INTERVALS_TIME = 100L; /** * 间隔时间内平移距离 */ private float mPanDistance = 0; /** * 间隔时间内平移增距 */ private float mIntervalIncreaseDistance = 0.5f; /** * 填满当前view所需bitmap个数 */ private int mBitmapCount = 0; /** * 是否开始滚动 */ private boolean mIsScroll; /** * 滚动方向，默认往上滚出 */ @ScrollOrientation private int mScrollOrientation; /** * 遮罩层颜色 */ @ColorInt private int mMaskLayerColor; private Drawable mDrawable; private Bitmap mSrcBitmap; private Paint mPaint; private Matrix mMatrix; public SrcScrollFrameLayout(@NonNull Context context) { this(context, null, 0); } public SrcScrollFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) { this(context, attrs, 0); } public SrcScrollFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); TypedArray array = context.getTheme().obtainStyledAttributes(attrs, R.styleable.SrcScrollFrameLayout, defStyleAttr, 0); int speed = array.getInteger(R.styleable.SrcScrollFrameLayout_speed, 3); mScrollOrientation = array.getInteger(R.styleable.SrcScrollFrameLayout_scrollOrientation, OUT_SLIDE_TOP); mIntervalIncreaseDistance = speed * mIntervalIncreaseDistance; mDrawable = array.getDrawable(R.styleable.SrcScrollFrameLayout_src); mIsScroll = array.getBoolean(R.styleable.SrcScrollFrameLayout_isScroll, true); mMaskLayerColor = array.getColor(R.styleable.SrcScrollFrameLayout_maskLayerColor, Color.TRANSPARENT); array.recycle(); setWillNotDraw(false); mPaint = new Paint(); mMatrix = new Matrix(); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); if (mDrawable == null || !(mDrawable instanceof BitmapDrawable)) { return; } if (getVisibility() == GONE) { return; } if (w == 0 || h == 0) { return; } if (mSrcBitmap == null) { Bitmap bitmap = ((BitmapDrawable) mDrawable).getBitmap(); //调整色彩模式进行质量压缩 Bitmap compressBitmap = bitmap.copy(Bitmap.Config.RGB_565, true); //缩放 Bitmap mSrcBitmap = scaleBitmap(compressBitmap); //计算至少需要几个 bitmap 才能填满当前 view mBitmapCount = scrollOrientationIsVertical() ? getMeasuredHeight() / mSrcBitmap.getHeight() + 1 : getMeasuredWidth() / mSrcBitmap.getWidth() + 1; if (!compressBitmap.isRecycled()) { compressBitmap.isRecycled(); System.gc(); } } } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); if (mSrcBitmap == null) { return; } int length = scrollOrientationIsVertical() ? mSrcBitmap.getHeight() : mSrcBitmap.getWidth(); int measuredHeight = getMeasuredHeight(); int measuredWidth = getMeasuredWidth(); if (length + mPanDistance != 0) { //第一张图片未完全滚出屏幕 mMatrix.reset(); switch (mScrollOrientation) { case OUT_SLIDE_TOP: mMatrix.postTranslate(0, mPanDistance); break; case OUT_SLIDE_BOTTOM: mMatrix.postTranslate(0f, measuredHeight - length - mPanDistance); break; case OUT_SLIDE_LEFT: mMatrix.postTranslate(mPanDistance, 0); break; case OUT_SLIDE_RIGHT: mMatrix.postTranslate(measuredWidth - length - mPanDistance, 0f); break; } canvas.drawBitmap(mSrcBitmap, mMatrix, mPaint); } if (length + mPanDistance < (scrollOrientationIsVertical() ? measuredHeight : measuredWidth)) { //用于补充留白的图片出现在屏幕 for (int i = 0; i < mBitmapCount; i++) { mMatrix.reset(); switch (mScrollOrientation) { case OUT_SLIDE_TOP: mMatrix.postTranslate(0f, (i + 1) * length + mPanDistance); break; case OUT_SLIDE_BOTTOM: mMatrix.postTranslate(0f, measuredHeight - (i + 2) * length - mPanDistance); break; case OUT_SLIDE_LEFT: mMatrix.postTranslate((i + 1) * length + mPanDistance, 0f); break; case OUT_SLIDE_RIGHT: mMatrix.postTranslate(measuredWidth - (i + 2) * length - mPanDistance, 0f); break; } canvas.drawBitmap(mSrcBitmap, mMatrix, mPaint); } } //绘制遮罩层 if (mMaskLayerColor != Color.TRANSPARENT) { canvas.drawColor(mMaskLayerColor); } //延时重绘实现滚动效果 if (mIsScroll) { getHandler().postDelayed(mRedrawRunnable, DEFAULT_DRAW_INTERVALS_TIME); } } /** * 重绘 */ private Runnable mRedrawRunnable = new Runnable() { @Override public void run() { int length = scrollOrientationIsVertical() ? mSrcBitmap.getHeight() : mSrcBitmap.getWidth(); if (length + mPanDistance |
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