onTouchMove:移动的处理.
/** 移动的处理 **/
void onTouchMove(MotionEvent event) {
int left = 0, top = 0, right = 0, bottom = 0;
/** 处理拖动 **/
if (mode == MODE.DRAG) {
/** 在这里要进行判断处理，防止在drag时候越界 **/
/** 获取相应的l，t,r ,b **/
left = current_x - start_x;
right = current_x + this.getWidth() - start_x;
top = current_y - start_y;
bottom = current_y - start_y + this.getHeight();
/** 水平进行判断 **/
if (isControl_H) {
if (left >= 0) {
left = 0;
right = this.getWidth();
}
if (right <= screen_W) {
left = screen_W - this.getWidth();
right = screen_W;
}
} else {
left = this.getLeft();
right = this.getRight();
}
/** 垂直判断 **/
if (isControl_V) {
if (top >= 0) {
top = 0;
bottom = this.getHeight();
}
if (bottom <= screen_H) {
top = screen_H - this.getHeight();
bottom = screen_H;
}
} else {
top = this.getTop();
bottom = this.getBottom();
}
if (isControl_H || isControl_V)
this.setPosition(left, top, right, bottom);
current_x = (int) event.getRawX();
current_y = (int) event.getRawY();
}
/** 处理缩放 **/
else if (mode == MODE.ZOOM) {
afterLenght = getDistance(event);// 获取两点的距离
float gapLenght = afterLenght - beforeLenght;// 变化的长度
if (Math.abs(gapLenght) > 5f) {
scale_temp = afterLenght / beforeLenght;// 求的缩放的比例
this.setScale(scale_temp);
beforeLenght = afterLenght;
}
}
}
处理的逻辑比较繁多，但上诉代码大部分都已注释,我相信大家都看得懂,大家可以掌握原理后可以进行自己的逻辑处理.
下面我们看下缩放处理，因为考虑到越界与否.
setScale方法：
/** 处理缩放 **/
void setScale(float scale) {
int disX = (int) (this.getWidth() * Math.abs(1 - scale)) / 4;// 获取缩放水平距离
int disY = (int) (this.getHeight() * Math.abs(1 - scale)) / 4;// 获取缩放垂直距离
// 放大
if (scale > 1 && this.getWidth() <= MAX_W) {
current_Left = this.getLeft() - disX;
current_Top = this.getTop() - disY;
current_Right = this.getRight() + disX;
current_Bottom = this.getBottom() + disY;
this.setFrame(current_Left, current_Top, current_Right,
current_Bottom);
/***
* 此时因为考虑到对称，所以只做一遍判断就可以了。
*/
if (current_Top <= 0 && current_Bottom >= screen_H) {
Log.e("jj", "屏幕高度=" + this.getHeight());
isControl_V = true;// 开启垂直监控
} else {
isControl_V = false;
}
if (current_Left <= 0 && current_Right >= screen_W) {
isControl_H = true;// 开启水平监控
} else {
isControl_H = false;
}
}
// 缩小
else if (scale < 1 && this.getWidth() >= MIN_W) {
current_Left = this.getLeft() + disX;
current_Top = this.getTop() + disY;
current_Right = this.getRight() - disX;
current_Bottom = this.getBottom() - disY;
/***
* 在这里要进行缩放处理
*/
// 上边越界
if (isControl_V && current_Top > 0) {
current_Top = 0;
current_Bottom = this.getBottom() - 2 * disY;
if (current_Bottom < screen_H) {
current_Bottom = screen_H;
isControl_V = false;// 关闭垂直监听
}
}
// 下边越界
if (isControl_V && current_Bottom < screen_H) {
current_Bottom = screen_H;
current_Top = this.getTop() + 2 * disY;
if (current_Top > 0) {
current_Top = 0;
isControl_V = false;// 关闭垂直监听
}
}
// 左边越界
if (isControl_H && current_Left >= 0) {
current_Left = 0;
current_Right = this.getRight() - 2 * disX;
if (current_Right <= screen_W) {
current_Right = screen_W;
isControl_H = false;// 关闭
}
}
// 右边越界
if (isControl_H && current_Right <= screen_W) {
current_Right = screen_W;
current_Left = this.getLeft() + 2 * disX;
if (current_Left >= 0) {
current_Left = 0;
isControl_H = false;// 关闭
}
}
if (isControl_H || isControl_V) {
this.setFrame(current_Left, current_Top, current_Right,
current_Bottom);
} else {
this.setFrame(current_Left, current_Top, current_Right,
current_Bottom);
isScaleAnim = true;// 开启缩放动画
}
}
}
