小菜请教个问题，eoeandroid上没解决

[XueSeCaiHong]

刚刚接手安卓，环境搭建完了之后，按照书上新建的helloword程序，但是在运行的时候，虚拟机光能调用，不显示“helloworld”。下面错误提示是 。在网上找了好多答案，包括删除R.java文件，重启程序，删除buildpath的库文件。。。都解决不了问题。请高手们帮忙回答一下吧。
程序如下：
package helloword.a;

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;


public class HellowordActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView tv = new TextView(this);
tv.setText("Hello World");
setContentView(tv);
}
}


Console显示：
[2012-09-21 18:52:08 - helloword] ------------------------------
[2012-09-21 18:52:08 - helloword] Android Launch!
[2012-09-21 18:52:08 - helloword] adb is running normally.
[2012-09-21 18:52:08 - helloword] Performing helloword.a.HellowordActivity activity launch
[2012-09-21 18:52:08 - helloword] Automatic Target Mode: Preferred AVD '2.3.1' is not available. Launching new emulator.
[2012-09-21 18:52:08 - helloword] Launching a new emulator with Virtual Device '2.3.1'
[2012-09-21 18:52:10 - helloword] New emulator found: emulator-5554
[2012-09-21 18:52:10 - helloword] Waiting for HOME ('android.process.acore') to be launched...
[2012-09-21 18:52:53 - helloword] HOME is up on device 'emulator-5554'
[2012-09-21 18:52:53 - helloword] Uploading helloword.apk onto device 'emulator-5554'
[2012-09-21 18:52:53 - helloword] Installing helloword.apk...
[2012-09-21 18:53:26 - helloword] Installation failed due to invalid APK file!
[2012-09-21 18:53:26 - helloword] Please check logcat output for more details.
[2012-09-21 18:53:26 - helloword] Launch canceled!

因为没有基础，希望回答的能详细点。谢谢

[mimitracely]

[2012-09-21 18:53:26 - helloword] Installation failed due to invalid APK file!


根本安装不了，你重新建一个模拟器试试？
看看是什么报错，贴上来，

[ameyume]

先把TextView放在main.xml中，看看能不能显示hello world。

[b87936260]

manifest中minsdk太高了把

[dong3560]

根本安装不上。。。

[XueSeCaiHong]

没有解决问题啊

[小强1002]

看下应该是没问题的，运行了下也是对的
但是楼主：
"
setContentView(R.layout.main);
TextView tv = new TextView(this);
tv.setText("Hello World");
setContentView(tv);
"
这个写法是没错，建议不要这么搞 养成好习惯么