我从 Android ActivityForResult 发送一个 parcelable 类并收到 null

Question

对不起，常见问题，但我检查了所有并找不到错误。我从 Activity 发送类并接收 NULL。创建 Intent 后检查是否正确（我的代码中为 readbackCi）。你能帮我找到解决办法吗？

我的班级 CityItem

import android.os.Parcel;
import android.os.Parcelable;

public class CityItem implements Parcelable {
public static final String ITEM_SEP = System.getProperty("line.separator");
public static final String NAME = "City";
public static final String REGNAME = "Region";
public static final String CODE = "Code";
public static final String SEARCH = "Search";

private String mName;
private String mRegName;
private String mSearch;
private String mCode;

public CityItem(String name, String regname, String code, String search) {
    mName = name;
    mRegName = regname;
    mSearch = search;
    mCode = code;
}

private CityItem(Parcel in) {
    in.readParcelable(CityItem.class.getClassLoader());
    setName(in.readString());
    setRegName(in.readString());
    setCode(in.readString());
    setSearch(in.readString());
}

public String getName() {
    return mName;
}

public void setName(String name) {
    mName = name;
}

public String getRegName() {
    return mRegName;
}

public void setRegName(String regname) {
    mRegName = regname;
}

public String getCode() {
    return mCode;
}

public void setCode(String code) {
    mRegName = code;
}

public String getSearch() {
    return mSearch;
}

public void setSearch(String search) {
    mRegName = search;
}

public String toString() {
    return mName + ITEM_SEP + mRegName + ITEM_SEP + mCode + ITEM_SEP
            + mSearch;
}

public String toLog() {
    return "Name:" + mName + ITEM_SEP + "Region:" + mRegName
            + ITEM_SEP + "Code:" + mCode + ITEM_SEP + "Search:"
            + mSearch + "\n";
}

@Override
public int describeContents() {
    return 0;
}

@Override
public void writeToParcel(Parcel dest, int flags) {
    dest.writeStringArray(new String[] { mName, mRegName, mCode, mSearch });
}

public static final Parcelable.Creator<CityItem> CREATOR = new Parcelable.Creator<CityItem>() {
    @Override
    public CityItem createFromParcel(Parcel source) {
            return new CityItem(source);
        }
    @Override
    public CityItem[] newArray(int size) {
        return new CityItem[size];
    }
};

}

第二次活动

public void enterClicked(CityItem str) {  
    Log.i(TAG,"Entered enterClicked()");
    Intent result = new Intent();
    result.putExtra("TAG", str);
    CityItem readbackCi = result.getParcelableExtra("TAG");
    Log.d(TAG, "\n\n\t" + readbackCi.NAME);
    setResult(this.RESULT_OK, result);

    finish();
}

主要活动

    @Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    Log.i(TAG, "Entered onActivityResult()");
    if(ADD_DERIVAL_REQUEST == requestCode && this.RESULT_OK == resultCode)
    {
        CityItem ci = (CityItem) getIntent().getParcelableExtra("TAG");
        if (null != ci) {
            EditText1.setText(ci.getName());                
        }
        return;
    } else if (ADD_DERIVAL_REQUEST == requestCode && RESULT_CANCELED == resultCode)
    {
        return;
    }
}

Answer 1

您需要使用Intent data 来获取结果。

CityItem ci = (CityItem) data.getParcelableExtra("TAG");

getIntent() 将返回用于主要活动启动的意图，它不是您感兴趣的意图。

Answer 2

parcelable 类 CityItem 的实现不正确。检查这个：

package com.mobgen.halo.android.sdk.generalcontent.business.parser;

import android.os.Parcel;
import android.os.Parcelable;

public class CityItem implements Parcelable {
    public static final String ITEM_SEP = System.getProperty("line.separator");
    public static final String NAME = "City";
    public static final String REGNAME = "Region";
    public static final String CODE = "Code";
    public static final String SEARCH = "Search";

    private String mName;
    private String mRegName;
    private String mSearch;
    private String mCode;

    public CityItem(String name, String regname, String code, String search) {
        mName = name;
        mRegName = regname;
        mSearch = search;
        mCode = code;
    }

    public String getName() {
        return mName;
    }

    public void setName(String name) {
        mName = name;
    }

    public String getRegName() {
        return mRegName;
    }

    public void setRegName(String regname) {
        mRegName = regname;
    }

    public String getCode() {
        return mCode;
    }

    public void setCode(String code) {
        mRegName = code;
    }

    public String getSearch() {
        return mSearch;
    }

    public void setSearch(String search) {
        mRegName = search;
    }

    public String toString() {
        return mName + ITEM_SEP + mRegName + ITEM_SEP + mCode + ITEM_SEP + mSearch;
    }

    public String toLog() {
        return "Name:" + mName + ITEM_SEP + "Region:" + mRegName
                + ITEM_SEP + "Code:" + mCode + ITEM_SEP + "Search:"
                + mSearch + "\n";
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(this.mName);
        dest.writeString(this.mRegName);
        dest.writeString(this.mSearch);
        dest.writeString(this.mCode);
    }

    protected CityItem(Parcel in) {
        this.mName = in.readString();
        this.mRegName = in.readString();
        this.mSearch = in.readString();
        this.mCode = in.readString();
    }

    public static final Creator<CityItem> CREATOR = new Creator<CityItem>() {
        public CityItem createFromParcel(Parcel source) {
            return new CityItem(source);
        }

        public CityItem[] newArray(int size) {
            return new CityItem[size];
        }
    };
}

除此之外，您必须使用“数据”Intent 而不是来自 getIntent() 的数据，后者是用于启动此活动的数据。