app/src/main/java/net/ktnx/mobileledger/ui/TextViewClearHelper.java

   1 /*
   2  * Copyright © 2020 Damyan Ivanov.
   3  * This file is part of MoLe.
   4  * MoLe is free software: you can distribute it and/or modify it
   5  * under the term of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your opinion), any later version.
   8  *
   9  * MoLe is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12  * GNU General Public License terms for details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with MoLe. If not, see <https://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.ktnx.mobileledger.ui;
  19
  20 import android.annotation.SuppressLint;
  21 import android.graphics.drawable.Drawable;
  22 import android.text.Editable;
  23 import android.text.TextWatcher;
  24 import android.view.MotionEvent;
  25 import android.view.View;
  26 import android.widget.EditText;
  27
  28 import net.ktnx.mobileledger.R;
  29
  30 public class TextViewClearHelper {
  31     private boolean hadText = false;
  32     private boolean hasFocus = false;
  33     private EditText view;
  34     private TextWatcher textWatcher;
  35     private View.OnFocusChangeListener prevOnFocusChangeListener;
  36     public void detachFromView() {
  37         if (view == null)
  38             return;
  39         view.removeTextChangedListener(textWatcher);
  40         prevOnFocusChangeListener = null;
  41         textWatcher = null;
  42         hasFocus = false;
  43         hadText = false;
  44         view = null;
  45     }
  46     @SuppressLint("ClickableViewAccessibility")
  47     public void attachToTextView(EditText view) {
  48         if (this.view != null)
  49             detachFromView();
  50         this.view = view;
  51         textWatcher = new TextWatcher() {
  52             @Override
  53             public void beforeTextChanged(CharSequence s, int start, int count, int after) {
  54
  55             }
  56             @Override
  57             public void onTextChanged(CharSequence s, int start, int before, int count) {
  58
  59             }
  60             @Override
  61             public void afterTextChanged(Editable s) {
  62                 boolean hasText = s.length() > 0;
  63
  64                 if (hasFocus) {
  65                     if (hadText && !hasText)
  66                         hideClearDrawable();
  67                     if (!hadText && hasText)
  68                         showClearDrawable();
  69                 }
  70
  71                 hadText = hasText;
  72
  73             }
  74         };
  75         view.addTextChangedListener(textWatcher);
  76         prevOnFocusChangeListener = view.getOnFocusChangeListener();
  77         view.setOnFocusChangeListener((v, hasFocus) -> {
  78             if (hasFocus) {
  79                 if (view.getText()
  80                         .length() > 0)
  81                 {
  82                     showClearDrawable();
  83                 }
  84             }
  85             else {
  86                 hideClearDrawable();
  87             }
  88
  89             this.hasFocus = hasFocus;
  90
  91             if (prevOnFocusChangeListener != null)
  92                 prevOnFocusChangeListener.onFocusChange(v, hasFocus);
  93         });
  94
  95         view.setOnTouchListener((v, event) -> this.onTouchEvent(view, event));
  96     }
  97     private void hideClearDrawable() {
  98         view.setCompoundDrawablesRelative(null, null, null, null);
  99     }
 100     private void showClearDrawable() {
 101         view.setCompoundDrawablesRelativeWithIntrinsicBounds(0, 0, R.drawable.ic_clear_accent_24dp,
 102                 0);
 103     }
 104     public boolean onTouchEvent(EditText view, MotionEvent event) {
 105         if ((event.getAction() == MotionEvent.ACTION_UP) && (view.getText()
 106                                                                  .length() > 0))
 107         {
 108             boolean clearClicked = false;
 109             final float x = event.getX();
 110             final int vw = view.getWidth();
 111             // start, top, end, bottom (end == 2)
 112             Drawable dwb = view.getCompoundDrawablesRelative()[2];
 113             if (dwb != null) {
 114                 final int dw = dwb.getBounds()
 115                                   .width();
 116                 if (view.getLayoutDirection() == View.LAYOUT_DIRECTION_LTR) {
 117                     if ((x > vw - dw))
 118                         clearClicked = true;
 119                 }
 120                 else {
 121                     if (x < vw - dw)
 122                         clearClicked = true;
 123                 }
 124                 if (clearClicked) {
 125                     view.setText("");
 126                     view.requestFocus();
 127                     return true;
 128                 }
 129             }
 130         }
 131
 132         return false;
 133     }
 134
 135 }