Java Android Studio显示数字和数学动作
tv和tv2应显示在“if”语句中写入的数学算法。 有人能帮我解决这个问题吗?如果单击按钮1,则在电视中显示数学动作,如果单击按钮2,则在电视中显示数学动作 MainActivity.java:Java Android Studio显示数字和数学动作,java,android,android-layout,Java,Android,Android Layout,tv和tv2应显示在“if”语句中写入的数学算法。 有人能帮我解决这个问题吗?如果单击按钮1,则在电视中显示数学动作,如果单击按钮2,则在电视中显示数学动作 MainActivity.java: package com.example.marek.przelicznikpaliw; import android.support.v7.app.ActionBarActivity; import android.os.Bundle; import android.view.Menu; import
package com.example.marek.przelicznikpaliw;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onButtonClick(View v){
//pola
EditText a1 = (EditText) findViewById(R.id.cel);
EditText b1 = (EditText) findViewById(R.id.pali);
EditText c1 = (EditText) findViewById(R.id.litr);
EditText d1 = (EditText) findViewById(R.id.koszt);
// wynik
TextView tv = (TextView) findViewById(R.id.wynikKoszt);
TextView tv2 = (TextView) findViewById(R.id.wynikKilometry);
float a,b,c,d,wynik;
a = Float.parseFloat(a1.getText().toString());
b = Float.parseFloat(b1.getText().toString());
c = Float.parseFloat(c1.getText().toString());
d = Float.parseFloat(d1.getText().toString());
wynik = 0;
if (v.getId() == R.id.button) {
wynik = ((b / 100) * a)*c;
} else if (v.getId() == R.id.button2) {
wynik = d/((b * c) / 100);
}
tv.setText(wynik+"");
tv2.setText(wynik+"");
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
activity_main.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity"
android:orientation="vertical"
android:onClick="onButtonClick">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/cel"
android:hint="Ilosc km do celu to:"
android:layout_centerHorizontal="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/pali"
android:hint="Ile litrow pali na 100km"
android:layout_centerHorizontal="true"
android:layout_below="@+id/cel" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/litr"
android:hint="Cena za litr"
android:layout_below="@+id/pali"
android:layout_centerHorizontal="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/button"
android:layout_below="@+id/litr"
android:layout_centerHorizontal="true"
android:hint="Licz zlotowki"
android:text="Licz koszty"
android:clickable="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/koszt"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:hint="Za ile zl zostalo zatankowane gaz/paliwo?" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Licz kilometry"
android:id="@+id/button2"
android:layout_below="@+id/koszt"
android:layout_centerHorizontal="true"
android:clickable="true" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/emptystring"
android:id="@+id/wynikKoszt"
android:textIsSelectable="true" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/emptystring"
android:id="@+id/wynikKilometry" />
</LinearLayout>
根据您给出的描述,我认为应该如下所示:
if (v.getId() == R.id.button) {
wynik = ((b / 100) * a)*c;
tv.setText(wynik+"");
tv2.setText("");
} else if (v.getId() == R.id.button2) {
wynik = d/((b * c) / 100);
tv2.setText(wynik+"");
tv.setText("");
}
这是您需要的吗?这应该可以:
public class MainActivity extends ActionBarActivity {
private EditText a1;
private EditText b1;
private EditText c1;
private EditText d1;
private TextView tv;
private TextView tv2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//pola
a1 = (EditText) findViewById(R.id.cel);
b1 = (EditText) findViewById(R.id.pali);
c1 = (EditText) findViewById(R.id.litr);
d1 = (EditText) findViewById(R.id.koszt);
// wynik
tv = (TextView) findViewById(R.id.wynikKoszt);
tv2 = (TextView) findViewById(R.id.wynikKilometry);
findViewById(R.id.button).setOnClickListener(onClickListener);
findViewById(R.id.button2).setOnClickListener(onClickListener);
}
private View.OnClickListener onClickListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
float a = 0;
float b = 0;
float c = 0;
float d = 0;
float wynik = 0;
try {
a = Float.parseFloat(a1.getText().toString());
b = Float.parseFloat(b1.getText().toString());
c = Float.parseFloat(c1.getText().toString());
d = Float.parseFloat(d1.getText().toString());
} catch (Exception e) {
e.printStackTrace();
}
if (view.getId() == R.id.button) {
wynik = ((b / 100) * a) * c;
tv.setText(String.valueOf(wynik));
} else if (view.getId() == R.id.button2) {
if((b * c == 0)){
Toast.makeText(MainActivity.this, "You can't divide by 0", Toast.LENGTH_LONG).show();
return;
}
wynik = d / ((b * c) / 100);
tv2.setText(String.valueOf(wynik));
}
}
};
}
C:\Users\Marek\AndroidStudioProjects\PrzelicznikPaliw\app\src\main\java\com\example\Marek\PrzelicznikPaliw\MainActivity.java错误:(55,6)错误:';'预期错误:任务执行失败:应用程序:CompiledBugJava'>编译失败;有关详细信息,请参阅编译器错误输出。信息:生成失败信息:总时间:2.494秒信息:2个错误信息:0警告信息:请参阅consoleif中的完整输出(view.getId()==R.id.button){wynik=((b/100)*a)*c;tv.setText(String.valueOf(wynik));}如果(view.getId()==R.id.button2){wynik=d/((b*c)/100);tv2.setText(String.valueOf(wynik));}}如果我这样设置,应用程序将无法运行,我将丢失一个;在
onClickListener
的末尾。我刚刚更新了答案,请再试一次。让我知道Przelicznik Paliw应用程序已冻结。或者你怎么说,这是用波兰语写的对不起,我不明白你最后的评论。你能澄清一下吗?在tv或tv2中不显示动作的值