android中自带计算器按.格式显示错误问题

来源：互联网发布：江苏省软件考试编辑：程序博客网时间：2024/06/04 18:59

在开发中遇到的关于android手机自带计算器显示格式纠正问题
此问题修改的文件路径：alps/packages/apps/Calculator/src/com/android/calculator2/CalculatorExpressionBuilder.java
replace()方法中做修改：
在switch循环后加入如下代码
        if(expr.length()>0){
       char mText=expr.charAt(expr.length()-1);
       Boolean mBoolean =false;
       if(!(mText==('0')||mText==('1')||mText==('2')||
           mText==('3')||mText==('4')||mText==('5')||
           mText==('6')||mText==('7')||mText==('8')||
           mText==('9'))){
           mBoolean=true;
       }
       android.util.Log.i("CalculatorExpressionBuilder","mBoolean="+mBoolean);
       if(appendExpr.equals(".")&&mBoolean){
            appendExpr="0.";
       }
          }else if(expr.length()==0&&appendExpr.equals(".")){
             appendExpr="0.";
          }
        }

此方法完整的代码所示
    @Override
    public SpannableStringBuilder replace(int start, int end, CharSequence tb, int tbstart,
            int tbend) {
        if (start != length() || end != length()) {
            mIsEdited = true;
            return super.replace(start, end, tb, tbstart, tbend);
        }

        String appendExpr =
                mTokenizer.getNormalizedExpression(tb.subSequence(tbstart, tbend).toString());
        if (appendExpr.length() == 1) {
            final String expr = mTokenizer.getNormalizedExpression(toString());
            // SPRD 515934 enter all numbers and operators, calculator crash
            final int len = expr.length();
            switch (appendExpr.charAt(0)) {
                case '.':
                    // don't allow two decimals in the same number
                    final int index = expr.lastIndexOf('.');
                    // SPRD: 544823 modify for StringIndexOutOfBoundsException
                    if (index != -1 && index < start && TextUtils.isDigitsOnly(expr.substring(index + 1, start))) {
                        appendExpr = "";
                    }
                    break;
                case '+':
                case '*':
                case '/':
                    // don't allow leading operator
                    if (start == 0) {
                        appendExpr = "";
                        break;
                    }
                    /*SPRD: Bug 487833 don't allow leading operator change from - to * or / @{ */
                    if (start == 1 && expr.equals("-")) {
                        appendExpr = "";
                        break;
                    }
                    /* @} */
                    /* SPRD 515934 enter all numbers and operators, calculator crash @{ */
                    Log.d("Calculator", "len: " + len + " start: " + start+" expr: "+expr);
                    if (start > len) {
                        break;
                    }
                    /* @} */
                    // don't allow multiple successive operators
                    while (start > 0 && "+-*/".indexOf(expr.charAt(start - 1)) != -1) {
                        --start;
                    }
                    // fall through
                case '-':
                    // don't allow -- or +-
                    // SPRD 515934 enter all numbers and operators,calculator crash
                    if ((start > 0) && (start <= len) && "+-".indexOf(expr.charAt(start - 1)) != -1) {
                        --start;
                    }

                    // mark as edited since operators can always be appended
                    mIsEdited = true;
                    break;
                default:
                    break;
            }
       if(expr.length()>0){
       char mText=expr.charAt(expr.length()-1);
       Boolean mBoolean =false;
       if(!(mText==('0')||mText==('1')||mText==('2')||
           mText==('3')||mText==('4')||mText==('5')||
           mText==('6')||mText==('7')||mText==('8')||
           mText==('9'))){
           mBoolean=true;
       }
       android.util.Log.i("CalculatorExpressionBuilder","mBoolean="+mBoolean);
       if(appendExpr.equals(".")&&mBoolean){
            appendExpr="0.";
       }
          }else if(expr.length()==0&&appendExpr.equals(".")){
             appendExpr="0.";
          }
        }

        // since this is the first edit replace the entire string
        if (!mIsEdited && appendExpr.length() > 0) {
            start = 0;
            mIsEdited = true;
        }

        appendExpr = mTokenizer.getLocalizedExpression(appendExpr);
        return super.replace(start, end, appendExpr, 0, appendExpr.length());
    }

0 0