由于两个空的编辑文本字段，我的安卓应用程序崩溃了

Question

    @Override
    public void onClick(View v)
    {
        float Percentage, newPercentage = 0;
        int Number;
        EditText Total = (EditText) findViewById(R.id.editText3);
        EditText Done = (EditText) findViewById(R.id.editText4);
        float num1 = Float.parseFloat(Total.getText().toString());
        float num2 = Float.parseFloat(Done.getText().toString());


        Percentage = (num2 / num1) * 100;
}
}

上面是我的代码，当我将其中任何一个留空时，它会崩溃。如何克服它。

Answer 1

只需检查用户是否输入了任何内容，然后解析您的值：

if(!Total.getText().toString().matches(""))
    float num1 = Float.parseFloat(Total.getText().toString());

Answer 2

尝试使用 try...抓住

 float num1 = 0.00f;
 float num2 = 0.00f;
try {
   num1 = Float.parseFloat(Total.getText().toString());
   num2 = Float.parseFloat(Done.getText().toString());
   Percentage = (num2 / num1) * 100;
}
catch(NumberFormatException ex) {
    //Handle Non Float Exception
   Toast.makeText(getApplicationContext(), "Invalid input !",Toast.LENGTH_LONG).show();
}

Answer 3

试试这个

  button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
if(!Total.getText().toString().trim().equals("")&&!Done.getText().toString().trim().equals("")){
                 float num1 = Float.parseFloat(Total.getText().toString());
                float num2 = Float.parseFloat(Done.getText().toString());
             Percentage = (num2 / num1) * 100;}
            }
        });

Answer 4

如果 EditText 不为空，则可以应用条件，则代码将像这样运行

            float Percentage, newPercentage = 0;
            int Number;
            EditText Total = (EditText) findViewById(R.id.editText3);
            EditText Done = (EditText) findViewById(R.id.editText4);
            String total=Total.getText().toString();
            String done=Done.getText().toString();
            if (!total.isEmpty() && !done.isEmpty()) {
                float num1 = Float.parseFloat(Total.getText().toString());
                float num2 = Float.parseFloat(Done.getText().toString());

                Percentage = (num2 / num1) * 100;
            }else {
                Toast.makeText(OpenFile.this, "Fill values", Toast.LENGTH_SHORT).show();
            }

Answer 5

首先检查你是否正确找到编辑文本之后还要检查 isEmpty 条件以避免空指针异常

if (!editText1.getText().toString().isEmpty() && !editText2.getText().toString().isEmpty()){
    float num1 = Float.parseFloat(Total.getText().toString());
    float num2 = Float.parseFloat(Done.getText().toString());
}

Answer 6

检查空文本，如果不是空，则执行计算

  if(!Total.getText().toString().isEmpty() && !Done.getText().toString().isEmpty()){
                 float num1 = Float.parseFloat(Total.getText().toString());
                float num2 = Float.parseFloat(Done.getText().toString());
             Percentage = (num2 / num1) * 100;}
            }
        });