Home | History | Annotate | Download | only in calculator2 
      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.calculator2;
     18 
     19 import android.content.Context;
     20 import android.text.Editable;
     21 import android.text.Spanned;
     22 import android.text.method.NumberKeyListener;
     23 import android.util.AttributeSet;
     24 import android.view.animation.TranslateAnimation;
     25 import android.text.InputType;
     26 import android.widget.EditText;
     27 import android.widget.TextView;
     28 import android.widget.ViewSwitcher;
     29 import android.graphics.Rect;
     30 import android.graphics.Paint;
     31 
     32 /**
     33  * Provides vertical scrolling for the input/result EditText.
     34  */
     35 class CalculatorDisplay extends ViewSwitcher {
     36     // only these chars are accepted from keyboard
     37     private static final char[] ACCEPTED_CHARS =
     38         "0123456789.+-*/\u2212\u00d7\u00f7()!%^".toCharArray();
     39 
     40     private static final int ANIM_DURATION = 500;
     41     enum Scroll { UP, DOWN, NONE }
     42 
     43     TranslateAnimation inAnimUp;
     44     TranslateAnimation outAnimUp;
     45     TranslateAnimation inAnimDown;
     46     TranslateAnimation outAnimDown;
     47 
     48     private Logic mLogic;
     49     private boolean mComputedLineLength = false;
     50 
     51     public CalculatorDisplay(Context context, AttributeSet attrs) {
     52         super(context, attrs);
     53     }
     54 
     55     @Override
     56     protected void onFinishInflate() {
     57         super.onFinishInflate();
     58         Calculator calc = (Calculator) getContext();
     59         calc.adjustFontSize((TextView)getChildAt(0));
     60         calc.adjustFontSize((TextView)getChildAt(1));
     61     }
     62 
     63     @Override
     64     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
     65         super.onLayout(changed, left, top, right, bottom);
     66         if (!mComputedLineLength) {
     67             mLogic.setLineLength(getNumberFittingDigits((TextView) getCurrentView()));
     68             mComputedLineLength = true;
     69         }
     70     }
     71 
     72     // compute the maximum number of digits that fit in the
     73     // calculator display without scrolling.
     74     private int getNumberFittingDigits(TextView display) {
     75         int available = display.getWidth()
     76             - display.getTotalPaddingLeft() - display.getTotalPaddingRight();
     77         Paint paint = display.getPaint();
     78         float digitWidth = paint.measureText("2222222222") / 10f;
     79         return (int) (available / digitWidth);
     80     }
     81 
     82     protected void setLogic(Logic logic) {
     83         mLogic = logic;
     84         NumberKeyListener calculatorKeyListener =
     85             new NumberKeyListener() {
     86                 public int getInputType() {
     87                     // Don't display soft keyboard.
     88                     return InputType.TYPE_NULL;
     89                 }
     90 
     91                 protected char[] getAcceptedChars() {
     92                     return ACCEPTED_CHARS;
     93                 }
     94 
     95                 public CharSequence filter(CharSequence source, int start, int end,
     96                                            Spanned dest, int dstart, int dend) {
     97                     /* the EditText should still accept letters (eg. 'sin')
     98                        coming from the on-screen touch buttons, so don't filter anything.
     99                     */
    100                     return null;
    101                 }
    102             };
    103 
    104         Editable.Factory factory = new CalculatorEditable.Factory(logic);
    105         for (int i = 0; i < 2; ++i) {
    106             EditText text = (EditText) getChildAt(i);
    107             text.setBackgroundDrawable(null);
    108             text.setEditableFactory(factory);
    109             text.setKeyListener(calculatorKeyListener);
    110         }
    111     }
    112 
    113     @Override
    114     public void setOnKeyListener(OnKeyListener l) {
    115         getChildAt(0).setOnKeyListener(l);
    116         getChildAt(1).setOnKeyListener(l);
    117     }
    118 
    119     @Override
    120     protected void onSizeChanged(int w, int h, int oldW, int oldH) {
    121         inAnimUp = new TranslateAnimation(0, 0, h, 0);
    122         inAnimUp.setDuration(ANIM_DURATION);
    123         outAnimUp = new TranslateAnimation(0, 0, 0, -h);
    124         outAnimUp.setDuration(ANIM_DURATION);
    125 
    126         inAnimDown = new TranslateAnimation(0, 0, -h, 0);
    127         inAnimDown.setDuration(ANIM_DURATION);
    128         outAnimDown = new TranslateAnimation(0, 0, 0, h);
    129         outAnimDown.setDuration(ANIM_DURATION);
    130     }
    131 
    132     void insert(String delta) {
    133         EditText editor = (EditText) getCurrentView();
    134         int cursor = editor.getSelectionStart();
    135         editor.getText().insert(cursor, delta);
    136     }
    137 
    138     EditText getEditText() {
    139         return (EditText) getCurrentView();
    140     }
    141 
    142     Editable getText() {
    143         EditText text = (EditText) getCurrentView();
    144         return text.getText();
    145     }
    146 
    147     void setText(CharSequence text, Scroll dir) {
    148         if (getText().length() == 0) {
    149             dir = Scroll.NONE;
    150         }
    151 
    152         if (dir == Scroll.UP) {
    153             setInAnimation(inAnimUp);
    154             setOutAnimation(outAnimUp);
    155         } else if (dir == Scroll.DOWN) {
    156             setInAnimation(inAnimDown);
    157             setOutAnimation(outAnimDown);
    158         } else { // Scroll.NONE
    159             setInAnimation(null);
    160             setOutAnimation(null);
    161         }
    162 
    163         EditText editText = (EditText) getNextView();
    164         editText.setText(text);
    165         //Calculator.log("selection to " + text.length() + "; " + text);
    166         editText.setSelection(text.length());
    167         showNext();
    168     }
    169 
    170     void setSelection(int i) {
    171         EditText text = (EditText) getCurrentView();
    172         text.setSelection(i);
    173     }
    174 
    175     int getSelectionStart() {
    176         EditText text = (EditText) getCurrentView();
    177         return text.getSelectionStart();
    178     }
    179 
    180     @Override
    181     protected void onFocusChanged(boolean gain, int direction, Rect prev) {
    182         //Calculator.log("focus " + gain + "; " + direction + "; " + prev);
    183         if (!gain) {
    184             requestFocus();
    185         }
    186     }
    187 }
    188