Android仿360悬浮小球自定义view实现示例

下面我将为您详细讲解“Android仿360悬浮小球自定义view实现示例”的完整攻略，过程中将包含两个示例说明。

一、前置知识

在开始实现自定义view之前，需要掌握以下内容：

1. Android基础知识，如Activity、Fragment、View等的生命周期和使用方法。

2. 自定义View的基本知识，如View的绘制、事件处理、属性设置等。

3. Android的动画知识，如属性动画、补间动画等。

4. 熟练掌握Java编程语言。

二、实现自定义悬浮球

以下将介绍两种实现自定义悬浮球的方式。

1. 实现方式一

第一步：创建一个自定义的View类，并重写onDraw方法进行悬浮球的绘制。

public class FloatBallView extends View {
    private Paint mPaint;
    private float mBallRadius = 30;

    public FloatBallView(Context context) {
        super(context);
        init();
    }

    public FloatBallView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    private void init() {
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setColor(Color.RED);
        mPaint.setStyle(Paint.Style.FILL);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawCircle(mBallRadius, mBallRadius, mBallRadius, mPaint);
    }
}

第二步：在Activity或Fragment中引入自定义View。

public class MainActivity extends AppCompatActivity {
    private FloatBallView mFloatBallView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mFloatBallView = findViewById(R.id.float_ball_view);
    }
}

第三步：实现悬浮球拖拽功能

public class MainActivity extends AppCompatActivity {
    private FloatBallView mFloatBallView;
    private int lastX;
    private int lastY;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mFloatBallView = findViewById(R.id.float_ball_view);
        mFloatBallView.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                int x = (int) event.getRawX();
                int y = (int) event.getRawY();
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        lastX = x;
                        lastY = y;
                        break;
                    case MotionEvent.ACTION_MOVE:
                        int offsetX = x - lastX;
                        int offsetY = y - lastY;
                        floatBallMove(offsetX, offsetY);
                        lastX = x;
                        lastY = y;
                        break;
                }
                return false;
            }
        });
    }

    private void floatBallMove(int offsetX, int offsetY) {
        int left = mFloatBallView.getLeft() + offsetX;
        int top = mFloatBallView.getTop() + offsetY;
        int right = mFloatBallView.getRight() + offsetX;
        int bottom = mFloatBallView.getBottom() + offsetY;
        mFloatBallView.layout(left, top, right, bottom);
    }
}

1. 实现方式二

使用WindowManager实现悬浮球

public class FloatWindowManager {
    private static final String TAG = "FloatWindowManager";
    private static volatile FloatWindowManager sInstance;

    private WindowManager mWindowManager;
    private WindowManager.LayoutParams mLayoutParams;
    private FloatBallView mFloatBallView;
    private int mWidth;
    private int mHeight;

    private FloatWindowManager(Context context) {
        mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        mLayoutParams = new WindowManager.LayoutParams();
        mLayoutParams.format = PixelFormat.TRANSPARENT;
        mLayoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
                | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;
        mLayoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
        mLayoutParams.gravity = Gravity.START | Gravity.TOP;
        mLayoutParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
        mLayoutParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
        mFloatBallView = new FloatBallView(context);
        mFloatBallView.setOnTouchListener(new View.OnTouchListener() {
            private int lastX;
            private int lastY;

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                int x = (int) event.getRawX();
                int y = (int) event.getRawY();
                switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        lastX = x;
                        lastY = y;
                        break;
                    case MotionEvent.ACTION_MOVE:
                        int offsetX = x - lastX;
                        int offsetY = y - lastY;
                        windowMove(offsetX, offsetY);
                        lastX = x;
                        lastY = y;
                        break;
                }
                return false;
            }
        });
        mFloatBallView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(v.getContext(), "点击了悬浮球", Toast.LENGTH_SHORT).show();
            }
        });
    }

    public static FloatWindowManager getInstance(Context context) {
        if (sInstance == null) {
            synchronized (FloatWindowManager.class) {
                if (sInstance == null) {
                    sInstance = new FloatWindowManager(context);
                }
            }
        }
        return sInstance;
    }

    public void show() {
        mWindowManager.addView(mFloatBallView, mLayoutParams);
    }

    public void hide() {
        mWindowManager.removeView(mFloatBallView);
    }

    public void windowMove(int offsetX, int offsetY) {
        mLayoutParams.x += offsetX;
        mLayoutParams.y += offsetY;
        if (Math.abs(mWidth - mLayoutParams.x) < mFloatBallView.getWidth() * 2
                || Math.abs(mLayoutParams.x) < mFloatBallView.getWidth() * 2) {
            hide();
        }
        if (mLayoutParams.y < 0) {
            mLayoutParams.y = 0;
        }
        if (mLayoutParams.y + mFloatBallView.getHeight() > getScreenHeight()) {
            mLayoutParams.y = getScreenHeight() - mFloatBallView.getHeight();
        }
        mWindowManager.updateViewLayout(mFloatBallView, mLayoutParams);
    }

    private int getScreenWidth() {
        return mWindowManager.getDefaultDisplay().getWidth();
    }

    private int getScreenHeight() {
        return mWindowManager.getDefaultDisplay().getHeight();
    }
}

以上就是关于“Android仿360悬浮小球自定义view实现示例”的完整攻略，希望能对您有所帮助。