Drag ImageView Or Bitmap Upon Touch
I currently have something working where I can drag a box horizontally on the screen (what I want it to do). However, it works when you click ANYWH开发者_如何学运维ERE on the screen, and I want it to work only when the box has been clicked. I have tried implementing this in different ways, and I've looked all over the place and still remain lost. Can anybody help? I also can't figure out how a bitmap is placed (I'm using a bitmap right now as I can't for the life of me figure out how to implement the ImageView inside my SurfaceView). If I say my bitmap is placed at 0,0 will that place the bitmap according to its top left corner at 0,0? I also had an algorithm for stopping the box when it reached an edge, but I'll just have to rewrite that as I must have deleted it. Please if you can offer your knowledge I would GREATLY appreciate it
public class BoardView extends SurfaceView implements SurfaceHolder.Callback{
Context mContext;
private BoardThread thread;
private float box_x = 140;
private float box_y = 378;
ImageView i = (ImageView) findViewById(R.id.box_view);
Bitmap box =
(BitmapFactory.decodeResource
(getResources(), R.drawable.box));
private float boxWidth = box.getWidth();
private float boxHeight = box.getHeight();
public BoardView(Context context){
super(context);
//surfaceHolder provides canvas that we draw on
getHolder().addCallback(this);
// controls drawings
thread = new BoardThread(getHolder(),this);
//intercepts touch events
setFocusable(true);
}
@Override
public void onDraw(Canvas canvas){
canvas.drawColor(Color.WHITE);
//draw box and set start location
canvas.drawBitmap(box, box_x - (boxWidth/2),
box_y - (boxHeight/2), null);
}
@Override
public boolean onTouchEvent(MotionEvent event){
//boolean mode = false;
if(event.getAction() == MotionEvent.ACTION_DOWN){
//int x = (int)event.getX();
//int y = (int)event.getY();
//if (x > box_x && x < box_x + 29 && y > box_y && y < box_y + 30){
//mode = true;
box_x = (int)event.getX();
//}
}
if(event.getAction() == MotionEvent.ACTION_MOVE) {
//int x = (int)event.getX();
//int y = (int)event.getY();
//if (mode == true){
box_x = (int)event.getX();
//}
}
invalidate();
return true;
}
@Override
public void surfaceChanged(SurfaceHolder holder,
int format, int width, int height ){
}
@Override
public void surfaceCreated(SurfaceHolder holder){
thread.startRunning(true);
thread.start();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder){
thread.startRunning(false);
thread.stop();
}
}
Simply check the touch event x and y coordinate, and check if this x,y-combination is within the box's bounds. I can see you are on the right path by looking at your commented out code.
Do something like this:
RectF rect = new RectF(x,y, x + box.getWidth(), y+box.geHeight());
if(rect.contains(touchX, touchY)) {
// You hit the box, allow dragging...
}
Try this:
package teste.com.br.teste;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.view.MotionEvent;
import android.view.View;
import java.util.ArrayList;
import java.util.List;
/**
* Created by Tacila on 03/07
*/
public class Game extends View {
private Context context;
private BitmaptArrastavel bmArrastavel;
private BitmaptArrastavel bmArrastavel2;
private BitmaptArrastavel bmArrastavelTeste;
private List<BitmaptArrastavel> btms;
private BitmaptArrastavel[] btmsAtivas;
private BitmaptArrastavel[] lake;
private BitmaptArrastavel[] ativos;
private int qntDeItens = 5;
public Game(Context context) {
super(context);
this.context = context;
init();
}
public void init() {
btms = new ArrayList<BitmaptArrastavel>();
btmsAtivas = new BitmaptArrastavel[1];
ativos=new BitmaptArrastavel[1];
lake = new BitmaptArrastavel[3];
lake[0] = new BitmaptArrastavel(escalaBitmap(BitmapFactory.decodeResource(context.getResources(), R.drawable.cartadc)), 200);
lake[1] = new BitmaptArrastavel(escalaBitmap(BitmapFactory.decodeResource(context.getResources(), R.drawable.cartaao)), 210);
lake[2] = new BitmaptArrastavel(escalaBitmap(BitmapFactory.decodeResource(context.getResources(), R.drawable.cartake)), 220);
btms.add(bmArrastavel);
btms.add(bmArrastavelTeste);
btms.add(bmArrastavel2);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawRGB(0,0,139);
for(int i = 0; i<=2; i++){
lake[i].drawOnCanvas(canvas);
}
}
public void travarArr(float x, float y ){
for(int i = 0; i<=2 ; i++){
if(lake[i].isDentro(x,y)){
ativos[0]=lake[i];
}
}
}
public void destravarBitmap() {
ativos[0]=null;
}
public Bitmap escalaBitmap(Bitmap bm) {
return Bitmap.createScaledBitmap(bm, 200, 300, false);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
final int action = event.getActionMasked();
switch (action) {
case MotionEvent.ACTION_DOWN:
System.out.println("Dentro do MotionEvent.ActionDown");
travarArr(event.getX(),event.getY());
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
System.out.println("Dentro do MotionEvent.ActionUP e ActionCancel tenho q entrar no destrava ");
destravarBitmap();
break;
case MotionEvent.ACTION_MOVE:
System.out.println("Dentro do MotionEvent.ActionMove");
for(int i = 0; i<ativos.length;i++){
if(ativos[i]!=null){
ativos[i].mover((int)event.getX(),(int)event.getY());
invalidate();
}
}
break;
case MotionEvent.ACTION_POINTER_DOWN:
System.out.println("Dentro do MotionEvent.ActionPointerDown");
travarArr(event.getX(), event.getY());
break;
case MotionEvent.ACTION_POINTER_UP:
System.out.println("Dentro do MotionEvent.ActionPointerUp");
destravarBitmap();
break;
default:
return super.onTouchEvent(event);
}
return true;
}
// int rotation = 0;
//
// public Bitmap vertical() {
// Matrix matrix = new Matrix();
// matrix.postRotate(90);
// Bitmap bm = escalaBitmap(BitmapFactory.decodeResource(context.getResources(), R.drawable.carta4c));
// return Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);
// }
}
The class BitmapArrastavel
package teste.com.br.teste;
import android.graphics.Bitmap;
import android.graphics.Canvas;
/**
* Created by Tacila on 05/07/2017.
*/
public class BitmaptArrastavel {
public int x, y, altura, largura;
private Bitmap bitmap;
public BitmaptArrastavel(Bitmap b, int x) {
bitmap = b;
this.x = x;
init();
}
public void init() {
largura = 200;
altura = 350;
}
public Bitmap escalaBitmap(Bitmap bm) {
return Bitmap.createScaledBitmap(bm, largura, altura, false);
}
public boolean isDentro(float x, float y) {
return (x >= this.x && x <= this.x + largura && y >= this.y && y <= this.y + altura);
}
public void drawOnCanvas(Canvas canvas) {
canvas.drawBitmap(bitmap, x, y, null);
}
public void mover(int x, int y) {
this.x = x;
this.y = y;
}
}
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