我想知道为什么我的计算器应用程序上的输出会给我这个消息?
我似乎总是看起来很简单。我认为可能是输出错误的EditTexts或解析我不需要的东西。除了将数字限制为两位小数,我可以找到一个修复,但我想我还是会问。任何提示都会受到赞赏,对于android编程来说还是一个新手。
package com.filej.calculatorapp;
import android.support.v4.media.MediaBrowserServiceCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class CalculatorApp extends AppCompatActivity` {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculator_app);
EditText heightEdit = (EditText) findViewById(R.id.heightEdit);
EditText widthEdit = (EditText) findViewById(R.id.widthEdit);
TextView area = (TextView) findViewById(R.id.areaTextView);
TextView perimeter = (TextView) findViewById(R.id.perimeterTextView);
Button calculate = (Button) findViewById(R.id.calculateButton);
View view = findViewById(R.id.calculateButton);
view.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
EditText height = (EditText) findViewById(R.id.heightEdit);
EditText width = (EditText) findViewById(R.id.widthEdit);
calculateArea(height.getText().toString(), width.getText().toString());
calculatePerimeter(height.getText().toString(), width.getText().toString());
}
});
}
private void calculateArea(String cHeight, String cWidth)
{
TextView area = (TextView) findViewById(R.id.areaTextView);
int area1 = Integer.parseInt(Height)* Integer.parseInt(Width);
area.setText(String.valueOf(area));
}
private void calculatePerimeter (String dHeight, String dWidth)
{
TextView perimeter = (TextView) findViewById(R.id.perimeterTextView);
int perimeter1 = (Integer.parseInt(Height) * 2) + (Integer.parseInt(Width) * 2);
perimeter.setText(String.valueOf(perimeter));
}
}
这是我的XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_calculator_app"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.filej.calculatorapp.CalculatorApp">
<TextView
android:text="Width"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="33dp"
android:id="@+id/textView2" />
<TextView
android:text="Height"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="40dp"
android:id="@+id/textView"
android:layout_below="@+id/textView2"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<TextView
android:text="Area"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="81dp"
android:id="@+id/textView3"
android:layout_below="@+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="41dp"
android:id="@+id/textView4"
android:layout_below="@+id/textView3"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:text="Perimeter" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number|numberDecimal"
android:ems="10"
android:id="@+id/widthEdit"
android:layout_alignBaseline="@+id/textView2"
android:layout_alignBottom="@+id/textView2"
android:layout_centerHorizontal="true"
android:singleLine="false"
android:text="Enter Width" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number|numberDecimal"
android:ems="10"
android:id="@+id/heightEdit"
android:text="Enter Height"
android:layout_alignBaseline="@+id/textView"
android:layout_alignBottom="@+id/textView"
android:layout_alignLeft="@+id/widthEdit"
android:layout_alignStart="@+id/widthEdit" />
<TextView
android:text="Total Area"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="@+id/textView3"
android:layout_alignLeft="@+id/heightEdit"
android:layout_alignStart="@+id/heightEdit"
android:id="@+id/areaTextView"
android:layout_alignRight="@+id/heightEdit"
android:layout_alignEnd="@+id/heightEdit" />
<TextView
android:text="Total Perimeter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/perimeterTextView"
android:layout_alignBaseline="@+id/textView4"
android:layout_alignBottom="@+id/textView4"
android:layout_alignLeft="@+id/areaTextView"
android:layout_alignStart="@+id/areaTextView"
android:layout_alignRight="@+id/areaTextView"
android:layout_alignEnd="@+id/areaTextView" />
<Button
android:text="Button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView4"
android:layout_toRightOf="@+id/textView2"
android:layout_toEndOf="@+id/textView2"
android:layout_marginTop="52dp"
android:id="@+id/calculateButton" />
</RelativeLayout>
答案 0 :(得分:3)
你的听众不应该在你的计算按钮而不是那个视图吗?像这样的东西
calculate = (Button) findViewById(R.id.calculateButton);
calculate.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
EditText height = (EditText) findViewById(R.id.heightEdit);
EditText width = (EditText) findViewById(R.id.widthEdit);
calculateArea(height.getText().toString(), width.getText().toString());
calculatePerimeter(height.getText().toString(), width.getText().toString());
}
});
并且您还要使用错误的值设置textview并解析错误的变量,请尝试:
private void calculateArea(String cHeight, String cWidth)
{
TextView area = (TextView) findViewById(R.id.areaTextView);
int area1 = Integer.parseInt(cHeight)* Integer.parseInt(cWidth);
area.setText(String.valueOf(area1));
}
private void calculatePerimeter (String dHeight, String dWidth)
{
TextView perimeter = (TextView) findViewById(R.id.perimeterTextView);
int perimeter1 = (Integer.parseInt(dHeight) * 2) + (Integer.parseInt(dWidth) * 2);
perimeter.setText(String.valueOf(perimeter1));
}
答案 1 :(得分:1)
您的行area.setText(String.valueOf(area));
正在将文本设置为对象的名称。
答案 2 :(得分:1)
您为编辑文本设置了错误的文字
使用
area.setText(String.valueOf(area1));
和
perimeter.setText(String.valueOf(perimeter1));
而不是
area.setText(String.valueOf(area));
perimeter.setText(String.valueOf(perimeter));
在您的案例区域和周边是视图,area1和perimeter1是计算值