Question

您好我创建了Android应用..它使用json解析值。我想将json的这个值从一个活动传递给另一个活动。我创建了以下代码。

...活性1

public class WaitressActivity extends Activity {

    Button btnSearch;
    Button btnDisplay;
    Button slide;
    SimpleSideDrawer slide_me;
    Button close;
    RelativeLayout window;
    ImageView clickWindow;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        initActivity();

        clickWindow.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                Intent init = new Intent(WaitressActivity.this,
                        TaleActivity.class);
                init.putExtras("logo",s);
                startActivity(init);


            }
        });


}

public void jasonParser() {

        // Hashmap for ListView
        //ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();

        // Creating JSON Parser instance
        JASONParser jParser = new JASONParser();

        // getting JSON string from URL
        JSONObject json = jParser.getJSONFromUrl(url);

        try {
            // Getting Array of Contacts
            contacts = json.getJSONArray(TAG_RESULT);

            logo1=new String[contacts.length()];
            name1=new String[contacts.length()];
            distance1=new String[contacts.length()];
            // looping through All Contacts
            for (int i = 0; i < contacts.length(); i++) {
                JSONObject c = contacts.getJSONObject(i);

                logoCount=logoCount+1;
                // Storing each json item in variable
                String latitude = c.getString(TAG_LONGITUDE);
                String lognitute = c.getString(TAG_LATITUDE);
                storeid = c.getString(TAG_STOREID);
                storename = c.getString(TAG_STORENAME);
                logo = c.getString(TAG_LOGO);
                String city = c.getString(TAG_CITY);
                distance = c.getString(TAG_DISTANCE);
                String num = c.getString(TAG_NUM);

                logo1[i]=logo;
                name1[i]=storename;
                distance1[i]=distance;

                // creating new HashMap
//               HashMap<String, String> map = new HashMap<String, String>();
//              
//               // adding each child node to HashMap key => value
//               map.put(TAG_LONGITUDE, latitude);
//               map.put(TAG_LATITUDE, lognitute);
//               map.put(TAG_STOREID, storeid);
//               map.put(TAG_STORENAME, storename);
//               map.put(TAG_LOGO, logo);
//               map.put(TAG_DISTANCE, distance);
//              //
//              // // adding HashList to ArrayList
//               contactList.add(map);
            }
        } catch (JSONException e) {
            // e.printStackTrace();
        }

        for(int i=0;i<logoCount;i++){


        int distanceIntVlue = Integer.parseInt(distance1[i]);

        if (distanceIntVlue < 200 ) {

            distanceSecond.setText("Distance meter " + distanceIntVlue);
            nameSecond.setText(name1[0]);
            imageLoader.DisplayImage(logo1[0], clickWindow);
             s=logo1[0];

            if(i==1){
                int distanceIntVlue1 = Integer.parseInt(distance1[i]);
                distanceplace.setText("Distance meter " + distanceIntVlue1);
                name.setText(name1[1]);
                imageLoaderUp.DisplayImage(logo1[1], logoUp);
            }

            if(i==2){
                imageLoaderUp.DisplayImage(logo1[2], logoUnder);

            }
        }
        }




        //tale.showImage(logo);//       DownloadAndReadImage dImage = new DownloadAndReadImage();
//
//      clickWindow.setImageBitmap(dImage.readBitmapImage(logo));
        //
    }


public void initActivity() {
        btnSearch = (Button) findViewById(R.id.btnsearch);
        btnDisplay = (Button) findViewById(R.id.btndisplay);
        // Slider=(Button)findViewById(R.id.btnslide);
        close = (Button) findViewById(R.id.btnclose);
        window = (RelativeLayout) findViewById(R.id.popup);
        close.setVisibility(View.INVISIBLE);
        window.setVisibility(View.INVISIBLE);
        clickWindow = (ImageView) findViewById(R.id.ImageView01);
        name = (TextView) findViewById(R.id.name);
        distanceplace = (TextView) findViewById(R.id.place);
        nameSecond = (TextView) findViewById(R.id.namesecond);
        distanceSecond = (TextView) findViewById(R.id.placesecond);
        logoUp=(ImageView)findViewById(R.id.imageView1);
        logoUnder=(ImageView)findViewById(R.id.ImageView01);
    }
}

我的第二项活动是，

public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.tale);
//
        Intent intent = getIntent();
       if (null != intent) {
                       urllogo= intent.getStringExtra("StringName");
        }

但问题是，参数“urllogo”总是得到空值。我搜索并尝试了许多方法来做到这一点。但在每次我得到空值.. 任何人都可以帮助我谢谢你... ...

Answer 1

确保用于放置和获取Intent extras中的字符串的键匹配：

init.putExtras("mystring",someString);

和

intent.getStringExtra("mystring");

Answer 2

请检查您的代码。见下面一行

urllogo= intent.getStringExtra("logo");

OR

请检查变量“s”中的值，是否包含值或已经为空。

Answer 3

您可以将“徽标”设置为参考：

init.putExtras("logo",s);

您检索了“StringName”而不是“logo”：

urllogo= intent.getStringExtra("StringName");

在第二项活动中进行如下更改：

urllogo= intent.getStringExtra("logo");

将字符串值从一个活动传递到另一个活动

3 个答案: